After we moved to Sask, the Riders of course. And surprisingly, the Montreal Canadiens - who were widely hated in the praries - but got right away that this was a team that played as a team, and during the 6 team NHL era at least, had the most lopsided home/away record in sports. At that time they had also won > half the Stanley cups...
But my real passion as a child, going back before the move up north, was Ferrari - both the Grand Prix and long distance teams with Chris Ammon and Niki Lauda probably my favorite drivers. Had an air mail subscription to Motor Sport to stay current - although back then Road & Track covered racing much more than they do now.