July: The British Army's Special Air Service is formed.
July 1: Commercial TV authorized by the FCC. - NBC television begins commercial operation on WNBT on channel 1. The world's first legal TV commercial, for Bulova watches, occurs at 2:29 PM over WNBT before a baseball game between the Brooklyn Dodgers and Philadelphia Phillies. The 10-second spot displayed a picture of a clock superimposed on a map of the United States, accompanied by the voice-over "America runs on Bulova time." As a one-off special, the first quiz show called "Uncle Bee" was telecast on WNBT's inaugural broadcast day, followed later the same day by Ralph Edwards hosting the second game show broadcast on United States television, Truth or Consequences, as simulcast on radio and TV and sponsored by Ivory soap. Weekly broadcasts of the show commenced in 1956, with Bob Barker. - CBS television begins commercial operation on New York station WCBW (now WCBS-TV) on channel 2.
July 2: Empire of Japan calls up 1 million men for military service.
July 3: Joseph Stalin, in his first address since the German invasion, calls upon the Soviet people to carry out a "scorched earth" policy of resistance to the bitter end.
July 4: The Massacre of Polish scientists and writers is committed by Nazi German troops in the occupied Polish city of Lwów.
July 5: Operation Barbarossa: German troops reach the Dnieper River.
July 5-July 31: War is fought between Peru and Ecuador.
July 7: American forces take over the defense of Iceland from the British. - German troops take over Estonia from the Soviets.
July 10: Jedwabne pogrom: Local ethnic Poles massacre at least 340 Jewish residents of Jedwabne in occupied Poland.
July 13: Montenegro starts the second popular uprising in Europe against the Axis Powers (the first being the "February strike" against deportation of Jews in Amsterdam and surroundings on February 25, 1941).
July 14: Vichy France signs armistice terms ending all fighting in Syria and Lebanon.
July 17: Joe DiMaggio's 56 game hitting streak ends.
July 19: A BBC broadcast by "Colonel Britton" calls on the people of occupied Europe to resist the Nazis under the slogan "V for Victory". - The first episode The Midnight Snack in which Tom and Jerry are officially named, more than a year after their first production Puss Gets the Boot
July 23: Italian aircraft damage the British destroyer HMS Fearless which has to be sunk.
July 25: Introduction of Postal codes in Germany.
July 26: In response to the Japanese occupation of French Indochina, U.S. President Franklin D. Roosevelt orders the seizure of all Japanese assets in the United States. - General Douglas MacArthur is named commander of all U.S. forces in the Philippines; the Philippines Army is ordered nationalized by President Roosevelt.
July 31: Under instructions from Adolf Hitler, Nazi official Hermann Goering orders S.S. General Reinhard Heydrich to "submit to me as soon as possible a general plan of the administrative material and financial measures necessary for carrying out the desired Final Solution of the Jewish question." (source: Wikipedia)