- Jan 1 16th Rose Bowl: Southern California beats Pittsburgh, 47-11
- Jan 1 Claus von Stauffenberg promoted to 2nd lieutenant
- Jan 1 Jurgens & Van den Berg merge with Lever Brothers to form Unilever
Bonnie Meets Clyde
Jan 5 Bonnie Parker meets Clyde Barrow for the first time at Clarence Clay's house
"A Single Spark Can Start a Prairie Fire"
Jan 5 Mao Zedong writes the essay "A Single Spark Can Start a Prairie Fire" to criticize cadres not creating rural revolutionary base areas
- Jan 6 1st diesel engine automobile trip (in a Packard sedan) completed
Bradman's World Record Score
Jan 6 Australian cricket icon Don Bradman scores 452 not out for New South Wales v Queensland in Sydney; then world record individual score in a first-class match; runs scored in 415 minutes
- Jan 7 Edwin Justus Mayer's "Children of Darkness" premieres in NYC
- Jan 7 Marguerite Perey discovers francium (Fr), the last naturally occurring element to be found
Albert Kahn Soviet Architects
Jan 9 Architectural firm Albert Kahn Associates becomes the consulting architects for all industrial construction in the Soviet Union
Headley Scores 157
Jan 15 Brilliant West Indian cricket batsman George Headley scores 157 of 176 on debut on the 4th day of the drawn 1st Test against England in Bridgetown, Barbados
- Jan 18 -27°F (-33°C), Watts, Oklahoma (state record)
"The Nose"
Jan 18 Dmitri Shostakovich's satirical opera "The Nose" premieres in Leningrad
- Jan 20 1st radio broadcast of "Lone Ranger" (WXYZ-Detroit)
- Jan 21 Boston Bruins become first team in NHL history to score 100 goals in a season, in a 5-1 win over Chicago at Boston Garden; Cooney Weiland scores Bruins' 100th goal in their 26th game of the year
- Jan 22 -35°F (-37°C), Mount Carroll, Illinois (state record)
- Jan 23 Clyde Tombaugh photographs dwarf planet Pluto
- Jan 23 George Washington Birthplace National Monument, Virginia established
- Jan 23 WIS-AM (now WOMG) in Columbia SC begins radio transmissions
- Jan 24 John Mills scores New Zealand's 1st Test century in cricket, sharing a record 276 run opening stand with Stewie Dempster
Australian Men's Tennis Open
Jan 25 Australian Championships Men's Tennis: Edgar Moon wins his first and only Grand Slam singles title; beats fellow Australian Harry Hopman 6-3, 6-1, 6-3
- Jan 25 Australian Championships Women's Tennis, Melbourne: Daphne Akhurst Cozens wins 3rd straight Australian singles title; beats Sylvia Lance Harper 10-8, 2-6, 7-5
- Jan 26 Cleveland's Terminal Tower opens (52 stories)
Primo de Rivera Resigns
Jan 28 Spanish dictator Miguel Primo de Rivera resigns as Prime Minister of Spain after losing the support of his fellow military leaders and King Alfonso XIII
- Jan 30 Russia launches their 1st radiosonde - a battery-powered telemetry instrument carried into the atmosphere to measure various parameters and transmit them by radio to a ground receiver- from Pavlovsk, USSR.
"The Bathhouse"
Jan 30 Vladimir Mayakovsky's drama "The Bathhouse (Bunya)" premieres in Leningrad
- Jan 31 1st US glider flight from a dirigible, Lakehurst, New Jersey