The Mann Cup has been part of Canadian lacrosse for more than a century, but the championship being played today is significantly different from the competition that began in 1910.
The trophy predates box lacrosse itself. It began as a senior lacrosse trophy played under field lacrosse rules before evolving into Canada's national Senior A men's box lacrosse championship. Today, the Mann Cup brings together the champions of Ontario's Major Series Lacrosse and British Columbia's Western Lacrosse Association.
Its history connects multiple eras of the sport, from the field game of the early 20th century to the development of indoor lacrosse and the modern Senior A championship.
When Did The Mann Cup Begin?
The Mann Cup dates to 1910, when Sir Donald Mann donated the trophy for senior lacrosse competition.
The trophy emerged after the Minto Cup shifted toward junior competition and initially operated largely as a challenge trophy rather than the established East-vs.-West championship series familiar to modern fans.
One of the most interesting parts of Mann Cup history is that it was not originally a box lacrosse championship.
Early Mann Cups were played under field lacrosse rules. New Westminster became an early powerhouse, winning six consecutive championships from 1920-25 during the pre-box era. By the mid-1920s, a national-playdown structure had replaced the older challenge system.
When Did The Mann Cup Become A Box Lacrosse Championship?
The transformation of the Mann Cup followed the rise of indoor lacrosse in Canada.
The 1931 Mann Cup was the last played as field lacrosse. The indoor era began in 1932, with the early indoor championship staged at Maple Leaf Gardens.
That creates one of the most unusual facts about the competition: The Mann Cup is older than box lacrosse itself.
From there, the trophy developed into one of the defining prizes in Canadian box lacrosse.
Orillia won three consecutive championships from 1934-36, establishing one of the early dynasties of the indoor era. Peterborough later produced an even more significant run.
The Great Mann Cup Dynasties
From 1951-54, the Peterborough Trailermen won four consecutive Mann Cups. Major Series Lacrosse's history identifies Peterborough as the first indoor team to win four straight championships.
Decades later, Six Nations became another major part of Mann Cup history.
The Chiefs won three consecutive championships from 1994-96. They eventually returned to the top with titles in 2013, 2014 and 2016 before beginning another three-year run in 2023.
Six Nations won again in 2024 and 2025, giving the Chiefs two separate Mann Cup three-peats: 1994-96 and 2023-25.
The second run also demonstrated the depth behind the Chiefs' success. Cody Jamieson was Mann Cup MVP in 2023, Lyle Thompson earned the honor in 2024 and Ryan Smith won it in 2025.
Who Has Won The Most Mann Cups?
New Westminster is the historical leader with 24 Mann Cup championships.
Peterborough's various senior teams also represent one of the championship's great traditions, while Brampton ranks above the Chiefs' total entering the 2026 series.
Six Nations entered that series with nine championships: 1994, 1995, 1996, 2013, 2014, 2016, 2023, 2024 and 2025.
Historical team totals require some care because club names and franchises have changed over more than a century. Year-by-year championship results provide a clearer historical picture than simply grouping every title by modern franchise identity.
How Does The East-vs.-West Mann Cup Work?
The modern Mann Cup provides a direct national championship between Canada's leading traditional Senior A leagues.
Ontario teams compete in Major Series Lacrosse, with the MSL playoff champion advancing to the Mann Cup. British Columbia's Western Lacrosse Association determines the Western representative through its playoffs.
Those two champions then meet for the Mann Cup. The championship site alternates between Ontario and British Columbia rather than being played at a neutral location.
The championship is a best-of-seven series, with the first team to four victories winning the Mann Cup.
Why Does Winning The Mann Cup Matter?
The Mann Cup connects generations of Canadian lacrosse in a way few championships can.
The trophy has survived the transformation from field lacrosse to the indoor game, the rise and fall of different powerhouse clubs and the development of modern professional box lacrosse.
Senior A is separate from the professional National Lacrosse League, but there is substantial crossover. Many players compete professionally during the NLL season before returning to Canadian Senior A clubs during the summer, giving the Mann Cup a concentration of recognizable elite box lacrosse talent.
The championship also sits within a history much older than the trophy itself. Lacrosse has Indigenous origins and deep significance among Haudenosaunee and other Indigenous peoples, long predating organized Canadian championships and professional leagues.
More than a century after Sir Donald Mann donated the trophy, the basic stakes remain remarkably straightforward: the best of the East meets the best of the West for Canada's Senior A box lacrosse championship.