One of the best two-way defensemen of his era, Sylvio Mantha enjoyed plenty of individual and team success in 14 stellar NHL seasons. He spent most of his big-league tenure with the Montreal Canadiens, with whom he was an important component of three Stanley Cup teams.
Born and bred in the St. Henri district of Montreal, Mantha first made a name for himself as a right wing with the Notre Dame de Grace juniors in 1918-19. That was followed by apprenticeships with Verdun in the Intermediate Mount Royal Hockey League, Montreal Imperial Tobacco and Montreal Northern Electric in the city's industrial league and a short stint with the Montreal Nationales of the Quebec senior amateur league. Well-known coach Arthur Therrien made an indelible impression on Mantha while coaching him at Verdun.
Mantha's four goals in nine games with the Nationales impressed the Montreal Canadiens enough to sign him in December 1923. Although he broke into the Canadiens lineup as a forward, he was soon moved back to fill a void on the right side of the team's blue line. Montreal was also trying to add youth to their defense corps, as veterans Sprague Cleghorn and Billy Coutu were on the downside of their careers.
Later that season, Mantha gained his first exposure to Stanley Cup glory when he helped Montreal vanquish the Vancouver Maroons and the Calgary Tigers. Then Cleghorn was traded prior to the 1925-26 season, paving the way for Mantha to take a more prominent role on the team. Mantha became a fixture on the Habs defense, pairing with Western Canada Hockey League veteran Herb Gardiner. On November 20, 1928, Mantha scored the first-ever goal in Boston Garden in a 1-0 Canadiens triumph over the Bruins.
Arguably, Mantha's two most rewarding seasons were 1929-30 and 1930-31. He contributed to consecutive Stanley Cup triumphs and was named to the NHL Second All-Star Team both years. By this time, Mantha was entrenched as one of the most revered defensive defensemen in the game. Further satisfaction came from sharing this success with his younger brother Georges, who was a defenseman and left wing for the Canadiens from 1928 to 1941.
In 1935-36, Mantha took on a greater challenge by serving as the Canadiens' player-coach. Unfortunately, the club didn't fare well and missed out on post-season play for the first time in a decade. Late in the 1936-37 season, he was signed by the Boston Bruins, for whom he played his last four regular-season games as defensive insurance.
After retiring, Mantha tried his hand as a linesman and referee in the American Hockey League and the NHL. However, the grueling travel schedule of an on-ice official proved to be too much. Mantha decided to stay in Montreal and ply his trade as an amateur coach. He guided the Montreal Concordias until 1943, when he switched to the junior ranks. Mantha passed his wealth of experience on to young players on the Laval Nationales from 1943 to 1945, the Verdun Maple Leafs from 1945 to 1947 and the St. Jerome Eagles from 1947 to 1948.
By the end of the 1940s, Mantha was ready to make a clean break from the game. In 1960 he was elected to the Hockey Hall of Fame and he died in August 1974 in Montreal, scene of many of his fondest memories, on or off the ice.