Originally posted by poundlee
I am not a hockey fan but according to Wikipedia "The Toronto Maple Leafs were the first NHL team to retire a number. On February 14, 1934 prior to the first NHL all-star game the Leafs retired Ace Bailey’s #6"
Yes, I think that's correct. Ace Bailey was tragicially injured, ending his career, and his number #6 was retired. However, that number did not stay retired forever, because it was worn in the 1970s briefly, with the permission of Ace Bailey, it is important to note.
So there was indeed a retired number earlier than Morenz's #7, which has not been worn since.
Incidentally, the reason Babe Ruth had #3 and Gerhig #4 was because that was the order in which they batted. That's how the Yankees decided on numbers when they were first worn. Mickey Mantle later made #7 famous, but I think the first player to wear it for the Yankees was none other than Leo Durocher!