Early career Foyston was born in
Minesing, Ontario, in 1891. From 1908 to 1910, he played for the Barrie Athletic Club in the OHA Jr. league. In 1908–09, he scored 17 goals in 6 games. In 1910–11, Foyston played for the Barrie Athletic Club in the
OHA Sr. league and scored 14 goals in 6 games. The following season, he played for the
Toronto Eaton's, scoring 15 goals in 6 games in the regular season and 5 goals in 4 games in the playoffs. At the end of the 1911–12 season the Eaton's challenged the
Winnipeg Victorias for the
Allan Cup, as amateur champions of Canada, but the Toronto club was defeated over two games by an aggregate score of 5–24 (4–8, 1–16), and Foyston went scoreless in the series.
Toronto Blueshirts Foyston began his professional hockey career with the
National Hockey Association's
Toronto Blueshirts in
1912–13. In his first season with Toronto, he scored 8 goals in 16 games, and the Blueshirts finished fourth overall in the NHA standings. The following season, in
1913–14, he scored 16 goals in 19 regular season games, and one goal in two NHA playoff games against the
Montreal Canadiens, to help the Blueshirts win the NHA championship and claim the
Stanley Cup. In the
1914 Stanley Cup Final against the
PCHA's
Victoria Aristocrats, Foyston scored two goals, including the series-clincher for Toronto. The following season, in
1914–15, Foyston had 13 goals and 9 assists in 20 games, and Toronto finished fourth in the league standings.
Seattle Metropolitans At the beginning of the
1915–16 season, Foyston signed with the PCHA's
Seattle Metropolitans – along with his Toronto teammates
Hap Holmes,
Eddie Carpenter,
Jack Walker, and
Cully Wilson – where he would play for nine seasons, leading the league in goals twice. In his first season with Seattle, he had 13 points in 18 games. The following season, in
1916–17, he had 36 goals and 12 assists in 24 games. Seattle played in the
1917 Stanley Cup Final against the Montreal Canadiens, and Foyston scored seven goals and added three assists to help the Metropolitans win the Stanley Cup in four games. It was the first time an American team had won the Stanley Cup. Foyston was conscripted into the
Canadian Expeditionary Force on April 2, 1918, as part of the
First World War, however after a month he was released to join the
Royal Flying Corps. However he did not serve overseas, and with the war over in November 1918 returned to hockey without missing much time. In
1918–19, Foyston scored 15 goals in 18 regular season games, and three goals in two playoff games, as Seattle advanced to the
1919 Stanley Cup Final against the Canadiens. Foyston scored nine goals in five games before the series was abandoned (with the teams tied at 2–2 in a best-of-five series format) due to the
influenza epidemic. The Stanley Cup was not awarded that year. The following season, in
1919–20, Foyston scored 26 goals in 22 regular season games, and three goals in two playoff games, as Seattle advanced to the
1920 Stanley Cup Final. In the Finals, he had six goals in five games. ==Legacy and playing style==