Isaiah Thomas Lansdown (aka Thomas Lansdown) was born 1823 in Cricklade, Wiltshire, England to Richard Lansdown (c1796-1853) and Susan Unknown and died 1900 Parramatta, New South Wales, Australia of unspecified causes.
Isaiah Thomas Lansdown is shown in the records as either Isaiah Thomas Lansdown or Thomas Lansdown.
Isaiah Thomas's christening record and the 1841 census show that his father Richard was a baker at Cricklade in Wiltshire, born in Wiltshire.
Isaiah Thomas married in Sydney in 1852.
The birth registration is only found for Isaiah Thomas's first daughter born in Sydney in June 1853.
He may be the Thomas Lansdown who in 1855 was gold-mining in the area of Major's Creek, nearby to Bell's Creek. The Goulburn Herald and County of Argyle Advertiser in February 1855 shows a Thomas Lansdown, of Major's Creek, advertising in regard to a horse that had strayed. (Major's Creek was 100km from Goulburn and covered by the Goulburn newspaper as the largest settlement in that area).
The Empire newspaper of 17 September 1868 describes him as Thomas Lansdown, a (gold-)digger and farmer of Larbert, Braidwood, who had found some diamonds whilst digging for gold and taken these diamonds to Sydney. The diamonds were regarded as virtually worthless due to there being no diamond cutters in the country.
He was found in Grenville's Post Office directory of 1872 as Thomas Lansdown, a (gold-)miner living at Labert, Braidwood.
His daughter Louisa was buried at Braidwood Cemetary in 1873, parents' names Thomas Lansdown and Catherine McAra.
His daughter Eliza was buried at Braidwood Cemetary in 1876, parents' names Isaiah Thomas Lansdown and Catherine McAra.
After Eliza's death Isaiah moved his family to Goulburn.
His daughter Sarah Catherine married in Goulburn in 1877 and all her children were born there.
When his son Thomas married in December 1881 the marriage notice in the newspaper described Isaiah as "Thomas Lansdown, late of Goulburn".
His wife Catherine died at Leichhardt, Sydney, in 1896. Their son Thomas William Lansdown was living at Leichhardt during the period.
Isaiah died at Parramatta in 1900, and his death was registered under the name of Thomas Lansdown.
When his sons Thomas and Richard died in 1915 and 1913 respectively their father's name was given as Thomas Lansdown and their mother's name as Catherine McAra.
Children
| Name | Birth | Death | Joined with |
| Sarah Catherine Lansdown (1853-1944) | 27 June 1853 Sydney, New South Wales, Australia | 1944 North Sydney, New South Wales, Australia | Isaac Bushell (1852-1941) |
| Louisa R Lansdown (-1873) | 1873 Braidwood, New South Wales, Australia | ||
| Eliza A Lansdown (-1876) | 1876 Braidwood, New South Wales, Australia | ||
| Thomas William Lansdown (-1915) | 23 June 1915 Dulwich Hill, Sydney, New South Wales, Australia | Amelia Huckstepp (1859-1898) Mary Jane Atkins (1858-1932) | |
| Richard Edward Lansdown (-1913) | November 1913 Newtown, Sydney, New South Wales, Australia | Mary Walsh | |
Siblings