Which NHL player had his jersey number retired first in league history?

Ace Bailey was the first NHL player whose jersey number was retired by his team. The Toronto Maple Leafs retired Bailey’s number 6 on February 14, 1934, making it the first such retirement in NHL history.

Bailey’s playing career ended after a violent 1933 incident involving Boston Bruins defenseman Eddie Shore. Shore struck Bailey from behind after mistakenly believing Bailey had delivered a previous check. Bailey suffered a fractured skull and never played professional hockey again, though he eventually recovered.

The retirement took place during the Ace Bailey Benefit Game at Maple Leaf Gardens. The exhibition brought together the Maple Leafs and an NHL All-Star team to raise money for Bailey and his family. Toronto owner Conn Smythe announced that no future Maple Leafs player would wear number 6.

Bailey’s case is sometimes confused with a league-wide retirement. His number was retired by Toronto, not by every NHL team. The NHL later retired Wayne Gretzky’s number 99 across the league in 2000. Bailey also led the NHL in scoring in 1928–29 and was inducted into the Hockey Hall of Fame in 1975.