The Cup was donated to the National Hockey Association[1] by Canadian Senator Michael J. O'Brien in honour of his son, Ambrose O'Brien, who was credited with the formation of the National Hockey Association, the forerunner to the NHL.

These were NHA executives Harry Trihey, Emmett Quinn and T. Yates Foster.

In November 1921, it was announced that the Cup would be given over to the National Hockey League to be awarded annually to the NHL playoff champions.

NHL president Frank Calder arranged with Ambrose O'Brien a new deed of gift.

The Cup, which Calder had secured following the death of Montreal President George Kennedy, was then presented to the NHL champion Ottawa Senators.

[11] The Cup was not formally awarded from 1939 to 1943 and it would not be until 1944 that the winning teams from that period were inscribed on the trophy.