The 1916–17 NHA season was the eighth and final season of the National Hockey Association. Six teams were to play two half-seasons of ten games each, but this was disrupted and only four teams finished the season. The Montreal Canadiens defeated the Ottawa Senators in a playoff to win the NHA championship.
The NHA franchise of the dormant Shamrocks was taken back from its owner Eddie Livingstone and used by the Toronto 228th Battalion, which had a number of NHA hockey players who had enlisted for military service. Also known as the Northern Fusiliers, the team played wearing khaki military uniforms and was the league's most popular and highest scoring club until the regiment was ordered overseas in February 1917 and the team was forced to withdraw. A scandal ensued when several stars were subsequently discharged, not having to fight and alleged they had been promised commissions solely to play hockey. The NHA would sue the 228th Battalion club for its withdrawal, though ultimately did not succeed.
A dispute also erupted over the playing schedule. After the 228th suspended play, the Toronto Blueshirts club was suspended for the rest of the season by the league, and some of its players played for other clubs for the rest of the schedule. The league intended for the players to be returned at the end of the season to whoever would own the Toronto club then. As the sale did not take place, the league kept them. The owner of the Blueshirts would file several lawsuits over the league's actions, sparking the events that led to the founding of the National Hockey League (NHL).