Davidson was born and raised in Kingston, Ontario, and learned the game through his coach, James T. Sutherland.
 He first played in the Ontario Hockey Association (OHA) senior division in 1908–09 where, as a 17-year-old, he led the league with eight goals in four games.
 He joined the Kingston Frontenacs of the OHA junior division in 1909 where he emerged as a top player in the league.
 He was known for his shooting ability and was considered a strong backchecker.
Davidson served as team captain, and led the Frontenacs to OHA junior titles in 1910 and 1911.
 He was a standout in the 1911 championship, leading his team back from a 3–0 deficit to win the game.

After leaving the junior game, Davidson moved to Alberta where he played senior hockey for the Calgary Athletics.
He scored three goals in four regular season games and added another three goals in three playoff games.
The Athletics won the provincial championship, but were defeated by the Winnipeg Victorias for the Allan Cup.
While with the Calgary Athletics Davidson played defence (either point or cover point).

He returned to Ontario for the 1912–13 season when he was signed by the Toronto Blueshirts of the National Hockey Association (NHA).
 Davidson made his professional debut with Toronto in their season-opening loss to the Montreal Canadiens, and finished his rookie season with 19 goals in 20 games.
He started the season on defence (point), the same position he had played the previous season in Calgary, but was soon switched to right wing.

The Blueshirts named him team captain for the 1913–14 season, and he responded by finishing in the top ten in NHA goals with 23 and second in assists with 13.
 Tied atop the standings with the Montreal Canadiens after the regular season, the Blueshirts faced the Canadiens in a two-game, total-goal series for both the O'Brien Cup, the NHA championship, and control of the Stanley Cup, the Canadian championship.
 Following a 2–0 loss at Montreal, Davidson played a key role in Toronto's 6–0 victory in the return match.
He scored two goals, including Toronto's third which clinched the championship.
The title represented the first time a team from Toronto won the Stanley Cup.

The Blueshirts then immediately faced the Victoria Aristocrats of the Pacific Coast Hockey Association held in March 1914.
It was considered an unofficial challenge for the Stanley Cup as the Aristocrats failed to arrange the series with the Cup's trustees.
 Toronto emerged with three consecutive victories to win the series that was on occasion violent – Davidson was involved in a fight late in the third game that touched off a melee involving most players for both teams.
Davidson was born and raised in Kingston, Ontario, and learned the game through his coach, James T. Sutherland.  He first played in the Ontario Hockey Association (OHA) senior division in 1908–09 where, as a 17-year-old, he led the league with eight goals in four games.  He joined the Kingston Frontenacs of the OHA junior division in 1909 where he emerged as a top player in the league.  He was known for his shooting ability and was considered a strong backchecker. Davidson served as team captain, and led the Frontenacs to OHA junior titles in 1910 and 1911.  He was a standout in the 1911 championship, leading his team back from a 3–0 deficit to win the game.
After leaving the junior game, Davidson moved to Alberta where he played senior hockey for the Calgary Athletics. He scored three goals in four regular season games and added another three goals in three playoff games. The Athletics won the provincial championship, but were defeated by the Winnipeg Victorias for the Allan Cup. While with the Calgary Athletics Davidson played defence (either point or cover point).
He returned to Ontario for the 1912–13 season when he was signed by the Toronto Blueshirts of the National Hockey Association (NHA).  Davidson made his professional debut with Toronto in their season-opening loss to the Montreal Canadiens, and finished his rookie season with 19 goals in 20 games. He started the season on defence (point), the same position he had played the previous season in Calgary, but was soon switched to right wing.
The Blueshirts named him team captain for the 1913–14 season, and he responded by finishing in the top ten in NHA goals with 23 and second in assists with 13.  Tied atop the standings with the Montreal Canadiens after the regular season, the Blueshirts faced the Canadiens in a two-game, total-goal series for both the O'Brien Cup, the NHA championship, and control of the Stanley Cup, the Canadian championship.  Following a 2–0 loss at Montreal, Davidson played a key role in Toronto's 6–0 victory in the return match. He scored two goals, including Toronto's third which clinched the championship. The title represented the first time a team from Toronto won the Stanley Cup.
The Blueshirts then immediately faced the Victoria Aristocrats of the Pacific Coast Hockey Association held in March 1914. It was considered an unofficial challenge for the Stanley Cup as the Aristocrats failed to arrange the series with the Cup's trustees.  Toronto emerged with three consecutive victories to win the series that was on occasion violent – Davidson was involved in a fight late in the third game that touched off a melee involving most players for both teams.
Scotty Davidson