He represented Victoria South in the House of Commons of Canada from 1882 to 1887 as a Conservative member.
He was born in Drum, County Monaghan, the son of John Dundas, and came to the Province of Canada in 1848, settling in Peterborough.
In 1856, Dundas moved to Lindsay working in William Cluxton's dry goods store at the northeast corner of William and Kent Streets.
The dry goods store would operate under this name until 1870 when Cluxton sold his interest to Dundas.
Dundas was involved in the grain trade and also served as a director of the Midland Railway.