- Jan 1 4th Rose Bow, Tournament Park, Pasadena, California: Mare Island, USMC beats Camp Lewis, US Army, 19-7; MVP: Hollis Huntington, USMC
Event of Interest
Jan 2 After repeated clashes over pay with the Brooklyn Robins owner Charlie Ebbets, star right fielder and future Baseball Hall of Fame manager Casey Stengel is traded to the Pittsburgh Pirates

Casey Stengel
- Jan 2 Montreal Arena in Westmount, Quebec, the home rink of 4-time Stanley Cup winners the Montreal Wanderers burns down leading to the club disbanding
Event of Interest
Jan 12 Montreal Canadien's center Joe Malone scores 5 goals in a 9-4 win over Ottawa to become the first 20 goal scorer in NHL history; goes on to score 44 regular season goals

Joe Malone
- Feb 26 Stands at Hong Kong Jockey Club collapse & burn, killing 604
- Mar 2 Joe Malone goes scoreless in Montreal Canadiens' 5-3 season-ending loss to Toronto Arenas; finishes the first NHL season with 44 goals, a record that stands until 1944-45
- Mar 13 1st NHL championship: Toronto Arenas beat Montreal Canadiens, outscoring them 10-7 in a 2 game set
- Mar 18 Soccer team SON OF Meerssen forms
- Mar 30 Stanley Cup, Mutual Street Arena, Toronto, ON: Toronto Arenas (NHL) beat Vancouver Millionaires (PCHA), 2-1 for a 3-2 series victory; first series contested by the new NHL
- Apr 15 22nd Boston Marathon won by Camp Devens relay team; race run as relay for 10-man military teams
Event of Interest
Apr 18 Cleveland center fielder Tris Speaker turns an unassisted double play

Tris Speaker
- Apr 27 Giants' 9-0 winning start & Dodgers' 0-9 losing streak are stopped
- Apr 29 Tris Speaker ties career outfield record of 4 unassisted double plays
- Apr 30 Orange Nassau soccer team forms in Groningen
- May 11 44th Kentucky Derby: William Knapp on Exterminator wins in 2:10.8
- May 14 Sunday baseball is made legal in Washington, D.C.
- May 15 43rd Preakness: Johnny Loftus aboard War Cloud wins in 1:53.6
Event of Interest
May 15 Washington Senator Walter Johnson pitches 1-0, 18 inning game

Walter Johnson
- May 24 Cleveland Indians Stan Coveleski sets club record for most innings pitched (19) as the Indians beat the Yankees 3-2
- Jun 1 Excelsior Maassluis soccer team forms in Maassluis
- Jun 1 Chicago White Sox losing 5-4 against NY Yankees, load the bases in 9th with no outs; Chick Gandil lines to Frank Baker who turns a rare game winning triple play
- Jun 13 Phillies and Cards tie 8-8 in 19 innings
- Jun 22 US National Championship Women's Tennis, Forest Hills, NY: Molla Bjurstedt beats Eleanor Goss 6-4, 6-3 for her 4th consecutive US singles title
- Jun 23 Boston Red Sox Dutch Leonard's 2nd no-hitter beats Tigers, 5-0
- Jul 17 Longest errorless game, Cubs beat Phillies 2-1 in 21 innings
- Jul 19 Washington Senators catcher Eddie Ainsmith applies for draft deferment; Secretary of War, Newton D Baker rules baseball players not draft exempt but later moves date to 1 September; both leagues end regular season 2 September
- Aug 1 Pittsburgh and Boston Braves play a MLB record 20 scoreless innings before Pirates win, 2-0 in 21
- Aug 9 Reds manager Christy Mathewson suspects Hal Chase of taking bribes to fix games, and suspends him "for indifferent play"
- Aug 24 Chicago Cubs, win earliest pennent ever (season ended Sept 2)
- Aug 24 Sect Baker grants extended exemption to World Series players
- Aug 27 Christy Mathewson resigns as Reds manager to accept a commission as a captain in chemical warfare branch of Army
- Aug 28 Tris Speaker suspended for season due to assault on umpire Tom Connolly
- Aug 31 Boston Red Sox, win earliest AL pennent ever (season ended Sept 2)
- Sep 3 US National Championship Men's Tennis, Forest Hills NY: Robert Lindley Murray successfully defends title; beats Bill Tilden 6-3, 6-1, 7-5
- Sep 5 Due to WW I, 15th World Series begins a month early
- Sep 10 Players on both sides threaten to strike the World Series unless they are guaranteed $2,500 to the winners & $1,000 each for the losers
- Sep 11 Boston Red Sox beat Chicago Cubs, 4 games to 2 in 15th World Series
- Oct 18 NHL's Quebec Bulldogs sold to a Toronto businessman P. J. Quinn
- Dec 10 John Heyder becomes president of baseball's National League for the 2nd time
Boxing Title Fight
Dec 16 Jack Dempsey KOs Carl Morris in 14 seconds

Jack Dempsey
Event of Interest
Dec 28 Montreal's Georges Vezina becomes the first NHL goalie to record an assist during the Canadiens’ 6-3 win over the Toronto Arenas

Georges Vezina