US media reported that Zehaf-Bibeau was a convert to Islam, while Canadian sources told local media that the government considered him a "high-risk traveller", confiscating his passport to stop him from going abroad.
Court documents show Michael Zehaf-Bibeau was convicted of several petty crimes during the early 2000s, spending several days in jail.
He was charged in Quebec for crimes including credit card fraud and multiple counts of drugs possession.
In Vancouver in 2011 he was also charged with robbery and making threats. A psychiatric assessment at the time considered him fit to stand trial.
Zehaf-Bibeau grew up in Laval, a city north of Montreal in Quebec.
Canadian media said his father, Bulgasem Zehaf, was originally from Libya and ran a cafe in Montreal. His mother, Susan Bibeau, worked at Canada's Immigration and Refugee Board. The couple were said to have divorced in 1999.