Holy Roman Empire

The Holy Roman Empire (HRE; Heiliges Römisches Reich (HRR), Imperium Romanum Sacrum (IRS), Sacro Romano Impero (SRI)) was a realm that existed for about a millennium in Central Europe, ruled by a Holy Roman Emperor. Its character changed during the Middle Ages and the Early Modern period, when the power of the emperor gradually weakened in favour of the princes, especially under Habsburg rule. In its last centuries, its character became quite close to a loose union of territories.

In the empire's later years, its faltering cohesion and the fact that Imperial lands were primarily populated by Germans despite its official "Roman" title, led to the designation Holy Roman Empire of the German Nation by the 16th century.

It is also termed the German First Reich.

"Holy"
Although the term "sacrum" (i.e. "holy") in connection with the medieval Roman Empire did not appear until 1157 under Frederick I Barbarossa, it is Otto I (also known as Otto the Great and Otto the German), crowned King of Germany in 962, who is generally considered to have been the first Holy Roman Emperor (Römisch-Deutscher Kaiser). Otto was the first emperor of the realm that later became known as the Holy Roman Empire who was not a member of the earlier Carolingian dynasty. The last Holy Roman Emperor was Francis II, who abdicated and dissolved the Empire in 1806 during the Napoleonic Wars. In a decree following the 1512 Diet of Cologne, the name was officially changed to Holy Roman Empire of the German Nation (Heiliges Römisches Reich Deutscher Nation, Imperium Romanum Sacrum Nationis Germanicæ).

The multiethnic Empire's territorial extent varied over its history, but at its peak it encompassed the Kingdom of Germany, the Kingdom of Italy and the Kingdom of Burgundy; for much of its history the Empire consisted of hundreds of smaller sub-units, principalities, duchies, counties, Free Imperial Cities, as well as other domains. Despite its name, for most of its history the empire did not include Rome within its borders.

The territories and dominion of the Holy Roman Empire in terms of present-day states comprised Germany (except Southern Schleswig), Austria (except Burgenland), the Czech Republic, Switzerland and Liechtenstein, the Netherlands, Belgium, Luxembourg, and Slovenia (except Prekmurje), besides significant parts of eastern France (mainly Artois, Alsace, Franche-Comté, Savoy and Lorraine), northern Italy (mainly Lombardy, Piedmont, Emilia-Romagna, Tuscany, and South Tyrol), and western Poland (mainly Silesia, Pomerania, and Neumark).

History
Charlemagne was crowned Emperor of the Romans in 800 and was thus the forerunner of the Holy Roman Empire,  largely because he had inaugurated the tradition of imperial coronation by the Pope of the Catholic Church. This continued as a significant institution in the Holy Roman Empire until the 16th century. Charlemagne's policy of "renovatio Romanorum imperii" (reviving the Roman Empire) remained, at least in theory, the official position of the Empire until its end in 1806.

Formation
The Carolingian imperial crown was initially disputed among the Carolingian rulers of Western Francia (France) and Eastern Francia (Germany), with first the western king (Charles the Bald) and then the eastern (Charles the Fat) attaining the prize. However, after the death of Charles the Fat in 888 the Carolingian Empire broke asunder, never to be restored. According to Regino of Prüm, each part of the realm elected a "kinglet" from its own "bowels." After the death of Charles the Fat those who were crowned Emperors by the Pope controlled only territories in Italy. The last of such Emperors was Berengar I of Italy who died in 924.

The dukes of Alemannia, Bavaria, Franconia and Saxony elected Conrad I of the Franks, not a Carolingian, as their leader in 911. His successor, Henry (Heinrich) I the Fowler (r. 919–936), a Saxon elected at the Reichstag of Fritzlar in 919, achieved the acceptance of a separate eastern empire by the West Franks (still ruled by the Carolingians) in 921, calling himself Rex Francorum Orientalum (King of the East Franks). He founded the Ottonian dynasty.

Henry designated his son Otto, who was elected King in Aachen in 936, to be his successor. A marriage alliance with the widowed queen of Italy gave Otto control over that nation as well. His later coronation as Emperor Otto I (later called "the Great") in 962 would mark an important step, since from then on the Eastern Frankish realm– and not the West Frankish kingdom that was the other remainder of the Frankish kingdoms–would have the blessing of the Pope. Otto had gained much of his power earlier, when, in 955, the Magyars were defeated in the Battle of Lechfeld.

In contemporary and later writings, this coronation would also be referred to as translatio imperii, the transfer of the Empire from the Romans to a new Empire. The German Emperors thus thought of themselves as being in direct succession of those of the Roman Empire; this is why they initially called themselves Augustus. Still, they did not call themselves "Roman" Emperors at first, probably in order not to provoke conflict with the Roman Emperor in Constantinople. The term imperator Romanorum only became common under Conrad II (later than his crowning in 1027, thus in the early-middle 11th century) after the Great Schism.

High Middle Ages
In the early 11th century, the eastern kingdom was not "German" but a "confederation" of the old Germanic tribes of the Bavarians, Alemanns, Franks and Saxons. The Empire as a political union probably only survived because of the strong personal influence of King Henry the Saxon and his son, Otto. Although formally elected by the leaders of the Germanic tribes, they were actually able to designate their successors.

This changed after Henry II died in 1024 without any children. Conrad II, first of the Salian Dynasty, was then elected king in 1024 only after some debate. How exactly the king was chosen thus seems to be a complicated conglomeration of personal influence, tribal quarrels, inheritance and acclamation by those leaders that would eventually become the collegiate of Electors.

Already at this time the dualism between the "territories," then those of the old tribes rooted in the Frankish lands, and the King/Emperor, became apparent. Each king preferred to spend most time in his own homelands; the Saxons, for example, spent much time in palatinates around the Harz mountains, among them Goslar. This practice had only changed under Otto III (king 983, Emperor 996–1002), who began to utilise bishoprics all over the Empire as temporary seats of government. Also, his successors, Henry II, Conrad II and Henry III, apparently managed to appoint the dukes of the territories. It is thus no coincidence that at this time, the terminology changes and the first occurrences of a regnum Teutonicum (German Kingdom) are found.

Investiture Controversy
The glory of the Empire almost collapsed in the Investiture Controversy, in which Pope Gregory VII declared a ban on the practice of lay investiture, that is, the practice of secular leaders appointing Catholic clergy and investing them with the symbols of the bishopric. Since lay investiture allowed secular rulers a measure of control over the Church in a given area (and therefore, over the minds of a king's subjects), Henry IV saw this action by the Pope as a form of interference with Henry's authority. Henry IV (king 1056, Emperor 1084–1106) persuaded bishops under his control to excommunicate the Pope Gregory VII whom he famously addressed as "Hildebrand...Not Pope but false monk!" The Pope however, announced that the oaths of loyalty made to Henry by his vassals were no longer binding, since he'd been excommunicated. Suddenly, the emperor found himself with almost no political support and was forced to make the famous Walk to Canossa in 1077. Because this episode demonstrated the limits of any would-be ruler's power in Christendom, it had wide-reaching implications for the rest of the Medieval Period. Meanwhile, the German dukes had elected a second king, Rudolf of Swabia, whom Henry IV could only defeat after a three-year war in 1080. The mythical roots of the Empire were permanently damaged; the German king was humiliated. Most importantly though, the church was clearly an independent player in the political system of the Empire.

Under the Hohenstaufen
Conrad III came to the throne in 1138. He was the first ruler of the Hohenstaufen dynasty; the Hohenstaufen was to restore the glory of the Empire, albeit under the new conditions of the 1122 Concordat of Worms. It was Frederick I "Barbarossa" (king 1152, Emperor 1155–1190) who first called the Empire "holy," with which he intended to address mainly law and legislation.

Under Barbarossa, the idea of the "Romanness" of the Empire culminated again, which seemed to be an attempt to justify the Emperor's power independently of the (now strengthened) Pope. An imperial assembly at the fields of Roncaglia in 1158 explicitly reclaimed imperial rights at the advice of quattuor doctores of the emerging judicial facility of the University of Bologna, citing phrases such as princeps legibus solutus ("the emperor princeps is not bound by law") from the Digestae of the Corpus Juris Civilis. That the Roman laws were created for an entirely different system and didn't fit the structure of the Empire was obviously secondary; the point here was that the court of the Emperor made an attempt to establish a legal constitution.

Imperial rights had been referred to as regalia since the Investiture Controversy, but were enumerated for the first time at Roncaglia as well. This comprehensive list included public roads, tariffs, coining, collecting punitive fees and the investiture, the seating and unseating of office holders. These rights were now explicitly rooted in Roman Law, a far-reaching constitutional act; north of the Alps, the system was also now connected to feudal law, a change most visible in the withdrawal of the feuds of Henry the Lion in 1180 which led to his public banning. Barbarossa thus managed for a time to more closely bind the stubborn Germanic dukes to the Empire as a whole.

Another important constitutional move at Roncaglia was the establishment of a new peace (Landfrieden) for all of the Empire, an attempt to (on the one hand) abolish private feuds not only between the many local dukes, but on the other hand a means to tie the Emperor's subordinates to a legal system of jurisdiction and public prosecution of criminal acts– a predecessor concept of "rule of law," in modern terms, that was, at this time, not yet universally accepted.

In order to solve the problem that the emperor was (after the Investiture Controversy) no longer as able to use the church as a mechanism to maintain power, the Staufer increasingly lent land to ministerialia, formerly non-free service men, which Frederick hoped would be more reliable than local dukes. Initially used mainly for war services, this new class of people would form the basis for the later knights, another basis of imperial power.

Another new concept of the time was the systematic foundation of new cities, both by the emperor and the local dukes. These were partly caused by the explosion in population, but also to concentrate economic power at strategic locations, while formerly cities only existed in the shape of either old Roman foundations or older bishoprics. Cities that were founded in the 12th century include Freiburg, possibly the economic model for many later cities, and Munich.

The later reign of the last Staufer Emperor, Frederick II, was in many ways different from that of earlier Emperors. Still a child, he first reigned in Sicily, while in Germany, Barbarossa's second son Philip of Swabia and Henry the Lion's son Otto IV competed with him for the title of King of the Germans. After finally having been crowned emperor in 1220, he risked conflict with the pope when he claimed power over Rome; astonishingly to many, he managed to claim Jerusalem in a crusade in 1228 while still under the pope's ban.

While Frederick brought the mythical idea of the Empire to a last high point, he was also the one to initiate the major steps that led to its disintegration. On the one hand, he concentrated on establishing an innovative state in Sicily, with public services, finances, and other reforms. On the other hand, Frederick was the emperor who granted major powers to the German dukes in the form of two far-reaching privileges that would never be reclaimed by the central power. In the 1220 Confoederatio cum principibus ecclesiasticis, Frederick gave up a number of regalia in favour of the bishops, among them tariffs, coining, and fortification. The 1232 Statutum in favorem principum mostly extended these privileges to the other (non-clerical) territories (Frederick II was forced to give those privileges by a rebellion of his son, Henry). Although many of these privileges had existed earlier, they were now granted globally, and once and for all, to allow the German dukes to maintain order north of the Alps while Frederick wanted to concentrate on his homelands in Italy. The 1232 document marked the first time that the German dukes were called domini terræ, owners of their lands, a remarkable change in terminology as well.

The Teutonic Knights were invited to Prussia by Duke Konrad of Masovia to Christianise the Prussians in 1226. The monastic state of the Teutonic Order (Deutschordensstaat) and its later German successor states of Prussia never formally belonged to the Holy Roman Empire during its existence.

During the long stays of the Hohenstaufen emperors (1138–1254) in Italy, the German princes became stronger and facilitated a successful, peaceful eastward settlement of lands previously sparsely inhabited by West Slavs or uninhabited, by German farmers, traders and others. The gradual germanization of these lands was a complex phenomenon which should not be interpreted in terms of 19th century nationalism's bias. By the eastward settlement the empire's influence increased to eventually include Pomerania and Silesia - also due to intermarriage of the local, still mostly Slavic, rulers with German spouses.

Interregnum
After the death of Frederick II in 1250, none of the dynasties worthy of producing the king proved able to do so, and the leading dukes elected several competing kings. The time from 1246 (beginning with the election of Heinrich Raspe and William of Holland) to 1273, when Rudolph I of Habsburg was elected king, is commonly referred to as the Interregnum. During the Interregnum, much of what was left of imperial authority was lost, as the princes were given time to consolidate their holdings and become even more independent rulers.

In 1257, there occurred a double election which produced a situation that guaranteed a long interregnum. William of Holland had fallen the previous year, and Conrad of Swabia had died three years earlier. First, three electors (Palatinate, Cologne and Mainz) (being mostly of the Guelph persuasion) cast their votes for Richard of Cornwall who became the successor of William of Holland as king. After a delay, a fourth elector, Bohemia, joined this choice. However, a couple of months later, Bohemia and the three other electors Trier, Brandenburg and Saxony voted for Alfonso X of Castile, this being based on Ghibelline party. The realm now had two kings.

Changes in political structure
The 13th century also saw a general structural change in how land was administered, preparing the shift of political power towards the rising bourgeoisie at the expense of aristocratic feudalism that would characterize the Late Middle Ages.

Instead of personal duties, money increasingly became the common means to represent economic value in agriculture. Peasants were increasingly required to pay tribute for their lands. The concept of "property" began to replace more ancient forms of jurisdiction, although they were still very much tied together. In the territories (not at the level of the Empire), power became increasingly bundled: Whoever owned the land had jurisdiction, from which other powers derived. It is important to note, however, that jurisdiction at this time did not include legislation, which virtually did not exist until well into the 15th century. Court practice heavily relied on traditional customs or rules described as customary.

It is during this time that the territories began to transform themselves into predecessors of modern states. The process varied greatly among the various lands and was most advanced in those territories that were most identical to the lands of the old Germanic tribes, e.g. Bavaria. It was slower in those scattered territories that were founded through imperial privileges.

Rise of the territories after the Staufen
The difficulties in electing the king eventually led to the emergence of a fixed college of electors, the Kurfürsten, whose composition and procedures were set forth in the Golden Bull of 1356. This development probably best symbolises the emerging duality between Kaiser und Reich, emperor and realm, which were no longer considered identical. This is also revealed in the way the post-Staufen kings attempted to sustain their power. Earlier, the Empire's strength (and finances) greatly relied on the Empire's own lands, the so-called Reichsgut, which always belonged to the respective king (and included many Imperial Cities). After the 13th century, its relevance faded (even though some parts of it did remain until the Empire's end in 1806). Instead, the Reichsgut was increasingly pawned to local dukes, sometimes to raise money for the Empire but, more frequently, to reward faithful duty or as an attempt to civilise stubborn dukes. The direct governance of the Reichsgut no longer matched the needs of either the king or the dukes.

Instead, the kings, beginning with Rudolph I of Habsburg, increasingly relied on the lands of their respective dynasties to support their power. In contrast with the Reichsgut, which was mostly scattered and difficult to administer, these territories were comparably compact and thus easier to control. In 1282, Rudolph I thus lent Austria and Styria to his own sons.

With Henry VII, the House of Luxembourg entered the stage. In 1312, he was crowned as the first Holy Roman Emperor since Frederick II. After him all kings and emperors relied on the lands of their own family (Hausmacht): Louis IV of Wittelsbach (king 1314, emperor 1328–1347) relied on his lands in Bavaria; Charles IV of Luxembourg, the grandson of Henry VII, drew strength from his own lands in Bohemia. Interestingly, it was thus increasingly in the king's own interest to strengthen the power of the territories, since the king profited from such a benefit in his own lands as well.

Imperial reform
The "constitution" of the Empire was still largely unsettled at the beginning of the 15th century. Although some procedures and institutions had been fixed, for example by the Golden Bull of 1356, the rules of how the king, the electors, and the other dukes should cooperate in the Empire much depended on the personality of the respective king. It therefore proved somewhat fatal that Sigismund of Luxemburg (king 1410, emperor 1433–1437) and Frederick III of Habsburg (king 1440, emperor 1452–1493) neglected the old core lands of the empire and mostly resided in their own lands. Without the presence of the king, the old institution of the Hoftag, the assembly of the realm's leading men, deteriorated. The Reichstag as a legislative organ of the Empire did not exist yet. Even worse, dukes often went into feuds against each other that, more often than not, escalated into local wars.

Simultaneously, the Church was in a state of crisis too, with wide-reaching effects in the Empire. The conflict between several papal claimants (two anti-popes and the legitimate Pope) was only resolved at the Council of Constance (1414–1418); after 1419, much energy was spent on fighting the Hussites. The medieval idea of unifying all Christendom into a single political entity, of which the Church and the Empire were the leading institutions, began to decline.

With these drastic changes, much discussion emerged in the 15th century about the Empire itself. Rules from the past no longer adequately described the structure of the time, and a reinforcement of earlier Landfrieden was urgently called for. During this time, the concept of "reform" emerged, in the original sense of the Latin verb re-formare, to regain an earlier shape that had been lost.

When Frederick III needed the dukes to finance war against Hungary in 1486 and at the same time had his son, later Maximilian I elected king, he was presented with the dukes' united demand to participate in an Imperial Court. For the first time, the assembly of the electors and other dukes was now called Reichstag (to be joined by the Imperial Free Cities later). While Frederick refused, his more conciliatory son finally convened the Reichstag at Worms in 1495, after his father's death in 1493. Here, the king and the dukes agreed on four bills, commonly referred to as the Reichsreform (Imperial Reform): a set of legal acts to give the disintegrating Empire back some structure. Among others, this act produced the Imperial Circle Estates and the Reichskammergericht (Imperial Chamber Court); structures that would—to a degree—persist until the end of the Empire in 1806.

However, it took a few more decades until the new regulation was universally accepted and the new court actually began to function; only in 1512 would the Imperial Circles be finalised. The King also made sure that his own court, the Reichshofrat, continued to function in parallel to the Reichskammergericht. It is interesting to note that in this year, the Empire also received its new title, the Heiliges Römisches Reich Deutscher Nation ("Holy Roman Empire of the German Nation").

Reformation and Renaissance
In 1516, Ferdinand II of Aragon, grandfather of the future Holy Roman Emperor Charles V, died. Due to a combination of (1) the traditions of dynastic succession in Aragon, which permitted maternal inheritance with no precedence for female rule; (2) the insanity of Charles's mother, Joanna of Castile; and (3) the insistence by his remaining grandfather, Maximilian I, that he take up his royal titles, Charles initiated his reign in Castile and Aragon, a union which evolved into Spain, in conjunction with his mother. This ensured for the first time that all the realms of the Iberian peninsula (save for Portugal) would be united by one monarch under one nascent Spanish crown, with the founding territories retaining their separate governance codes and laws. In 1519, already reigning as Carlos I in Spain, Charles took up the imperial title as Karl V. The balance (and imbalance) between these separate inheritances would be defining elements of his reign, and would ensure that personal union between the Spanish and German crowns would be short-lived. The latter would end up going to a more junior branch of the Habsburgs in the person of Charles's brother Ferdinand, while the senior branch continued rule in Spain and in the Burgundian inheritance in the person of Charles's son, Philip II of Spain.

In addition to conflicts between his Spanish and German inheritances, conflicts of religion would be another source of tension during the reign of Charles V. Before Charles even began his reign in the Holy Roman Empire, in 1517, Martin Luther initiated what would later be known as the Reformation. At this time, many local dukes saw it as a chance to oppose the hegemony of Emperor Charles V. The empire then became fatally divided along religious lines, with the North, the East, and many of the major cities—Strasbourg, Frankfurt and Nuremberg—becoming Protestant while the southern and western regions largely remained Catholic.

From 1515 to 1523, the Habsburg government in the Netherlands also had to contend with the Frisian peasant rebellion, led first by Pier Gerlofs Donia and then by his nephew Wijerd Jelckama. The rebels were initially successful, but after a series of defeats, the remaining leaders were taken and decapitated in 1523. This was a blow for the Holy Roman Empire since many major cities were sacked and as many as 132 ships sunk (once even 28 in a single battle).

Baroque period
Charles V continued to battle the French and the Protestant princes in Germany for much of his reign. After his son Philip married Queen Mary of England, it appeared that France would be completely surrounded by Habsburg domains, but this hope proved unfounded when the marriage produced no children. In 1555, Paul IV was elected pope and took the side of France, whereupon an exhausted Charles finally gave up his hopes of a world Christian empire. He abdicated and divided his territories between Philip and Ferdinand of Austria. The Peace of Augsburg ended the war in Germany and accepted the existence of the Protestant princes, although not Calvinism, Anabaptism, or Zwingliism. Although the Holy Roman Empire would nominally exist until 1806, it effectively ceased to mean anything after 1555. Germany would enjoy relative peace for the next six decades. On the eastern front, the Turks continued to loom large as a threat, although war would mean further compromises with the Protestant princes, and so the emperor sought to avoid that. In the west, the Rhineland increasingly fell under French influence. And after the Dutch revolt against Spain erupted, the Empire remained neutral. A side effect of that conflict was the Cologne War, which ravaged much of the upper Rhine. After Ferdinand died in 1564, his son Maximilian II became emperor, and like his father, accepted the existence of Protestantism and the need for occasional compromise with it. Maximilian was succeeded in 1576 by Rudolf II, a strange man who preferred classical Greek philosophy to Christianity and lived an isolated existence in Bohemia. He became afraid to act when the Catholic Church was forcibly reasserting control in Austria and Hungary and the Protestant princes became upset over this. Imperial power sharply deteriorated by the time of Rudolf's death in 1612. When Bohemians rebelled against the emperor, the immediate result was the series of conflicts known as the Thirty Years' War (1618–1648), which devastated the Empire. Foreign powers, including France and Sweden, intervened in the conflict and strengthened those fighting Imperial power, but they also seized considerable chunks of territory for themselves. The long conflict bled the Empire to such a degree that it would never recover its former strength.

At the Battle of Vienna (1683), the army of the Holy Roman Empire led by Polish King John III Sobieski decisively defeated a large Turkish army, ending the western colonial Ottoman advance and leading to the eventual dismemberment of the Ottoman Empire in Europe. The HRE army was half Polish/Lithuanian Commonwealth forces, mostly cavalry, and half Holy Roman Empire forces (German/Austrian), mostly infantry. The cavalry charge was the largest in the history of warfare.

The actual end of the empire came in several steps. The Peace of Westphalia in 1648, which ended the Thirty Years' War, gave the territories almost complete sovereignty. The Swiss Confederation, which had already established quasi-independence in 1499, as well as the Northern Netherlands, left the empire. Although its constituent states still had some restrictions—in particular, they could not form alliances against the Emperor—the Empire from this point was a powerless entity, existing in name only. The Habsburg Emperors instead focused on consolidating their own estates in Austria and elsewhere.

Prussia and Austria
By the rise of Louis XIV, the Habsburgs were dependent on the position as Archdukes of Austria to counter the rise of Prussia, some of whose territories lay inside the Empire. Throughout the 18th century, the Habsburgs were embroiled in various European conflicts, such as the War of the Spanish Succession, the War of the Polish Succession and the War of the Austrian Succession. The German dualism between Austria and Prussia dominated the empire's history after 1740.

French Revolutionary Wars and final dissolution
From 1792 onwards, revolutionary France was at war with various parts of the Empire intermittently. The German Mediatisation was the series of mediatisations and secularisations that occurred in 1795–1814, during the latter part of the era of the French Revolution and then the Napoleonic Era.

Mediatisation was the process of annexing the lands of one sovereign monarchy to another, often leaving the annexed some rights. Secularisation was the redistribution to secular states of the secular lands held by an ecclesiastical ruler such as a bishop or an abbot.

The Empire was formally dissolved on 6 August 1806 when the last Holy Roman Emperor Francis II (from 1804, Emperor Francis I of Austria) abdicated, following a military defeat by the French under Napoleon (see Treaty of Pressburg). Napoleon reorganised much of the empire into the Confederation of the Rhine, a French satellite. Francis' House of Habsburg-Lorraine survived the demise of the Empire, continuing to reign as Emperors of Austria and Kings of Hungary until the Habsburg empire's final dissolution in 1918 in the aftermath of World War I.

The Napoleonic Confederation of the Rhine was replaced by a new union, the German Confederation, in 1815, following the end of the Napoleonic Wars. It lasted until 1866 when Prussia founded the North German Confederation, a forerunner of the German Empire which united the German-speaking territories outside of Austria and Switzerland under Prussian leadership in 1871. This later served as the predecessor-state of modern Germany.

Institutions
The Holy Roman Empire was not a highly centralized state like most countries today. Instead, it was divided into dozens—eventually hundreds—of individual entities governed by kings, dukes, counts, bishops, abbots or other rulers, collectively known as princes. There were also some areas ruled directly by the Emperor. At no time could the Emperor simply issue decrees and govern autonomously over the Empire. His power was severely restricted by the various local leaders.

From the High Middle Ages onwards, the Holy Roman Empire was marked by an uneasy coexistence of the princes of the local territories who were struggling to take power away from it. To a greater extent than in other medieval kingdoms such as France and England, the Emperors were unable to gain much control over the lands that they formally owned. Instead, to secure their own position from the threat of being deposed, Emperors were forced to grant more and more autonomy to local rulers, both nobles and bishops. This process began in the 11th century with the Investiture Controversy and was more or less concluded with the 1648 Peace of Westphalia. Several Emperors attempted to reverse this steady dissemination of their authority, but were thwarted both by the papacy and by the princes of the Empire.

Imperial estates
The number of territories in the Empire was considerable, rising to approximately 300 at the time of the Peace of Westphalia. Many of these Kleinstaaten ("little states") covered no more than a few square miles, or included several non-contiguous pieces, so the Empire was often called a Flickenteppich ("patchwork carpet").

An entity was considered a Reichsstand (imperial estate) if, according to feudal law, it had no authority above it except the Holy Roman Emperor himself. The imperial estates comprised:
 * Territories ruled by a hereditary nobleman, such as a prince, archduke, duke, or count.
 * Territories in which secular authority was held by a clerical dignitary, such as an archbishop, bishop, or abbot. Such a cleric was a prince of the church. In the common case of a prince-bishop, this temporal territory (called a prince-bishopric) frequently overlapped with his often-larger ecclesiastical diocese, giving the bishop both civil and clerical powers. Examples include the three prince-archbishoprics: Cologne, Trier, and Mainz.
 * Free imperial cities, which were subject only to the jurisdiction of the emperor.

For a list of Reichsstände in 1792, see List of Reichstag participants (1792).

King of the Romans
A prospective Emperor had first to be elected King of the Romans (Latin: Rex romanorum; German: römischer König). German kings had been elected since the 9th century; at that point they were chosen by the leaders of the five most important tribes (the Salian Franks of Lorraine, Ripuarian Franks of Franconia, Saxons, Bavarians and Swabians). In the Holy Roman Empire, the main dukes and bishops of the kingdom elected the King of the Romans. In 1356, Emperor Charles IV issued the Golden Bull, which limited the electors to seven: the Count Palatine of the Rhine, the King of Bohemia, the Duke of Saxony, the Margrave of Brandenburg and the archbishops of Cologne, Mainz, and Trier. During the Thirty Years' War, the Duke of Bavaria was given the right to vote as the eighth elector. A candidate for election would be expected to offer concessions of land or money to the electors in order to secure their vote.

After being elected, the King of the Romans could theoretically claim the title of "Emperor" only after being crowned by the Pope. In many cases, this took several years while the King was held up by other tasks: frequently he first had to resolve conflicts in rebellious northern Italy, or was in quarrel with the Pope himself. Later Emperors dispensed with the papal coronation altogether, being content with the styling Emperor-Elect: the last Emperor to be crowned by the Pope was Charles V in 1530.

The Emperor had to be a man of good character over 18 years. All four of his grandparents were expected to be of noble blood. No law required him to be a Catholic, though imperial law assumed that he was. He did not need to be a German (Alfonso X of Castile was not). By the 17th century candidates generally possessed estates within the Empire.

Reichstag
The Reichstag, or Reichsversammlung, was the legislative body of the Holy Roman Empire and theoretically superior to the emperor himself. It was divided into three classes. The first class, the Council of Electors, consisted of the electors, or the princes who could vote for King of the Romans. The second class, the Council of Princes, consisted of the other princes. The Council of Princes was divided into two "benches," one for secular rulers and one for ecclesiastical ones. Higher-ranking princes had individual votes, while lower-ranking princes were grouped into "colleges" by geography. Each college had one vote.

The third class was the Council of Imperial Cities, which was divided into two colleges: Swabia and the Rhine. Each college had one collective vote. The Council of Imperial Cities was not fully equal to the others; it could not vote on several matters such as the admission of new territories. The representation of the Free Cities at the Reichstag had become common since the late Middle Ages. Nevertheless, their participation was formally acknowledged only as late as in 1648 with the Peace of Westphalia ending the Thirty Years' War.

Imperial courts
The Empire also had two courts: the Reichshofrat (also known in English as the Aulic Council) at the court of the King/Emperor, and the Reichskammergericht (Imperial Chamber Court), established with the Imperial Reform of 1495.

Imperial circles
As part of the Imperial Reform, six Imperial Circles were established in 1500; four more were established in 1512. These were regional groupings of most (though not all) of the various states of the Empire for the purposes of defence, imperial taxation, supervision of coining, peace-keeping functions and public security. Each circle had its own parliament, known as a Kreistag ("Circle Diet"), and one or more directors, who coordinated the affairs of the circle. Not all imperial territories were included within the imperial circles, even after 1512; the Lands of the Bohemian Crown were excluded, as were Switzerland, the imperial fiefs in northern Italy, the lands of the Imperial Knights, and certain other small territories like the Lordship of Jever.

Maps

 * The Holy Roman Empire, 1138–1254
 * The Holy Roman Empire c. 1500
 * The Holy Roman Empire in 1648
 * The Holy Roman Empire in 1789 (interactive map)