It is on the eastern side of the Nepean River, just south of Penrith and bears the name of Thomas Jamison, a pioneer landowner and First Fleet surgeon.

Prior to European settlement, what is now Jamisontown was home to the Mulgoa people who spoke the Darug language.

Later, the property passed to his son, Sir John Jamison (1776–1844), Kt, MD, MLC - a celebrated physician, land owner and political reformer, who erected a splendid mansion (since destroyed by fire) on the nearby Regentville estate during the 1820s.

At a local government level, Jamisontown is part of the south ward of Penrith City Council, represented by Jim Aitken, Mark Davies, Karen McKeown, Susan Page and Gary Rumble.

At the state level, it is part of the Electoral district of Penrith, represented by Liberal Stuart Ayres.