Jim Brady was born in 1908 at Lake St. Vincent (near St. Paul, Alberta). His father was a wealthy storekeeper of Scottish ancestry. His mother (Metis) was Philomena Archange, a registered nurse. Brady grew up in St. Paul which was the largest Metis community in Alberta at that time. The militant ideologies of the community were to have a tremendous influence on Brady's life.

While he was growing up, the Brady family were strong advocates of Metis identity and social equality. As a young man, Brady was tutored by various politicians, activists and union supporters. During the 1920s he worked as a labourer and became knowledgeable about the politics of work and the prairies.

In 1930 Brady became a Marxist. Intent on social equality, he joined Malcolm Norris, Pete Tomkins and Joseph Dion in the 30s. Together they formed the Metis Association of Alberta. When war broke out, he was refused entrance into the army because of his communist affiliations. Brady continued his political struggles until he was finally accepted into the army in 1943.

After the war, Brady moved to Northern Saskatchewan. He lived in a simple log cabin lined with scholarly books and he worked as a prospector to support himself. He was reunited with Norris and together they worked to organize the Northern Metis Association in Saskatchewan. Brady was viewed as the strategist.

In 1967, while on a prospecting expedition with a Cree friend, Brady and his partner disappeared. An extensive Royal Canadian Mounted Police search ensued, but they were never found. Many Metis believe that the two men were murdered for political reasons.