In 1915, Canadian Football consisted of three separate leagues: the IRFU (Interprovincial Rugby Football Union), the ORFU (Ontario Rugby Football Union), and the CIRFU (Intercollegiate Rugby Football Union). However, the CIRFU suspended all football operations as a result of World War I. As a result, only the IRFU and the ORFU participated during the 1915 season. This would also be the last season for Canadian football until after World War I was completed in 1919. During the regular season, the teams in each league would play each other, but not the teams from the other two leagues. In the IRFU, the Hamilton Tigers would run away with the league championship with a perfect 6-0 record. Meanwhile, Toronto RAA and the Hamilton Rowing Club would finish tied in the ORFU with an identical 2-2 record. Although both teams officially qualified for the playoffs, the Hamilton Rowing Club would decline participation in the post-season, paving the way for Toronto RAA to participate in the 7th Grey Cup Championship. The Hamilton Tigers won their second Grey Cup in three years in a controversial 13-7 win over the Toronto Rowing and Athletic Association. Toronto outplayed Hamilton on a wet and slippery Varsity Stadium field in the first half. Despite this, Toronto RAA could only manage a 4-1 lead at halftime. George Bickle booted a field goal for Toronto in the first quarter. The Tigers came out charging in the second half, and before they knew it, Toronto was down 7-4. Jack Erskine carried the ball 15 yards around the end for a try, which was converted by Sam Manson. Before the end of the third quarter Hal DeGruchy kicked a pair of lengthy punts for rouges to cut the Toronto deficit to 7-6. But the Tigers scored the winning points in the fourth quarter on a controversial touchdown when Lutz found an opening and squeezed through for a try. Toronto's wings gave up on the play believing an offside interference penalty would be called. It was not, and Hamilton had a 12-6 advantage. Toronto RAA had a golden opportunity to tie the score when an onside kick gave them the ball on Hamilton's one-yard line. But the Tigers held their ground on three straight plays, stuffing Toronto's opportunity. Both teams traded rouges to end the scoring. The usually subdued Toronto crowd was so enraged with a referee following the game, that a mob of people went after him to give him a verbal lashing. The police stepped in before things got out of control, and ushered him into the safety of the Toronto RAA dressing room. In a move that confused some people in later years, the Tigers had a shield made for the Grey Cup
in honour of their 1908 championship team. This was, in part, revenge against the University of Toronto for holding onto the trophy in years which it did not win the Dominion championship in 1912 and 1913. The 1908 shield still remains attached to the original base of the trophy. With the First World War raging in Europe, both teams donated their share of the gate receipts to patriotic funds. It was the last time the Grey Cup was contested until after the war.