- Sep 1 British New Guinea placed under Australian administration
- Sep 1 Canadian province of Alberta adopts Mountain Standard Time
- Sep 1 New York Highlanders win their 6th consecutive MLB game in 3 days from Washington Senators; sweep AL record 3 straight double headers
- Sep 1 Philadelphia beats the Red Sox 4-1 in 24 innings in Boston in the longest game in AL baseball history; both starters go the distance as A's hurler Jack Coombs overcomes Boston's Joe Harris
- Sep 1 The International Federation of Intellectual Property Attorneys (FICPI) is established
- Sep 3 After an 8 minute argument over an umpire call the NY Highlanders win on forfeit over Philadelphia A's; Highlanders' MLB record 5th doubleheader sweep on consecutive days
- Sep 3 Philadelphia Giants win Negro Championship Cup in Philadelphia before 10,000 fans; black baseball's largest crowd ever
- Sep 4 New York Highlanders beat Boston Pilgrims, 7 - 0 and 1 - 0 for their MLB record 5th straight doubleheader sweep
- Sep 5 Saint Louis University quarterback Bradbury Robinson throws first legal forward pass in the history of American football for a TD to Jack Schneider at Carroll College, Waukesha, Wisconsin; Saint Louis wins, 22-0
Satyagraha
Sep 11 Mahatma Gandhi coins the term "Satyagraha" to characterize the Non-Violence movement in South Africa
- Sep 12 The Newport Transporter Bridge is opened in Newport, South Wales by Viscount Tredegar.
- Sep 13 1st airplane flight in Europe, Brazilian Alberto Santos-Dumont test flies his hybrid 14-bis plane (attached to a hydrogen balloon for take-off), at Bagatelle, France
- Sep 16 Kaarlo Nieminen wins 1st Finnish marathon
Eddie Collins Debut
Sep 17 Playing as "Sullivan" Columbia University jr Eddie Collins debuts with A's
- Sep 18 A typhoon with tsunami kills an estimated 10,000 people in Hong Kong
- Sep 20 Cunard Line's RMS Mauretania is launched at the Swan Hunter & Wigham Richardson shipyard in Newcastle, England.
- Sep 21 New York Highlanders 1st baseman Hal Chase has 22 put-outs to tie MLB record in a 6-3 win over Chicago White Sox at South Side Park
- Sep 22 In New Zealand Domestic workers call for a 68-hour working week
- Sep 22 Race riot in Atlanta Georgia, kills 21
- Sep 24 Prince George of Greece, convinced that he can no longer serve the cause of Crete, resigns as High Commissioner
- Sep 24 St Louis Card Stony McGlynn no-hits Dodgers, 1-1 in 7 inning game
- Sep 24 Victor Herbert and Henry Blossom's operetta musical "The Red Mill" opens at the Knickerbocker Theater, NYC
- Sep 25 John Galsworthy's "Silver Box" premieres in London
- Sep 25 Leonardo Torres Quevedo successfully demonstrates the Telekino at Bilbao before a great crowd, guiding a boat from the shore, considered the birth of the remote control
- Sep 26 Pitts Lefty Leifield no-hits Phillies, 8-0 in 6 inning game
- Sep 28 US troops reoccupy Cuba, stay until 1909
- Sep 29 US intervenes in Cuba ousts dictator Estrada Palma
- Sep 30 Real Academia Galega, Galician language biggest linguistic authority starts working in Havana
Authors
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