[1] McLennan was born in Crieff, Perthshire, Scotland, the son of Peter McLellan and Margaret, née Sim.
[2] When gold was discovered by Edward Hargraves, he went to Summer Hill and Turon diggings, New South Wales, and worked with some success.
Returning to Victoria in July 1851, on discovery of gold there, he went to Ballarat and Forest Creek, and was amongst the first pioneers of Bendigo, where he worked at Golden Gully.
In 1857, the time of the Canton Lead, he proceeded to Ararat, where fifty thousand miners were collected, and was elected a member of the Mining Board.
[2] McLellan represented Ararat till the general election in May 1877, when he was beaten by David Gaunson by five votes.