[1] McCallum, born in Tiree, Argyllshire, Scotland, was a contractor and shipowner before entering politics as a Liberal-Conservative.

He represented the riding of Monck in the House of Commons of Canada from 1867 to 1872, when he was defeated by James David Edgar.

In the subsequent byelection, McCallum again defeated Edgar, this time by a mere 4 votes.

Robb and fought with his men against the Fenians in Fort Erie on the afternoon of June 2.

Outnumbered 10 to 1, McCallum and sixteen other men fought their way out of Fort Erie before being rescued by the Robb.