January 4: Culbert Olson, 29th Governor of California, is succeeded by Earl Warren.

January 11: The United States and United Kingdom give up territorial rights in China.

January 13: 36 people are executed and 200 arrested in anti-Nazi protests in Sofia.

January 15: Guadalcanal Campaign - Operation Ke: Japanese forces begin to withdraw from Guadalcanal in the Solomon Islands. - The world's largest office building, The Pentagon, is dedicated in Arlington, Virginia.

January 16: Iraq declares war on the Axis powers.

January 18: Soviet officials announce that the Red Army has broken the Wehrmacht's siege of Leningrad as part of Operation Iskra, opening a narrow land corridor to the city. Georgy Zhukov is promoted to Marshal of the Soviet Union. - The Warsaw Ghetto Uprising begins.

January 23: British forces capture Tripoli from the Italians. - Duke Ellington plays at New York City's Carnegie Hall for the first time. - Critic and commentator Alexander Woollcott suffers an eventually fatal heart attack during a regular broadcast of the CBS Radio roundtable program People's Platform.

January 27: 50 bombers mount the first all American air raid against Germany; Wilhelmshaven is the target.

January 29: Nazi German police arrest alleged necrophiliac and serial killer Bruno Lüdke. - United States Marine Corps Women's Reserve (MCWR) created.

January 29-30 - Battle of Rennell Island - The Imperial Japanese Navy resists the United States Navy's attempt to interrupt the withdrawal of Japanese forces from Guadalcanal in the last major naval battle of the Guadalcanal Campaign.

January 29-31 - Battle of Wau - Australian forces with United States support resist a Japanese advance in the New Guinea campaign. (source: Wikipedia)