thumb|Allied troops land on the beaches of Normandy during D-Day. thumb|LVTs heading for shore on June 15, 1944, during the Battle of Saipan. June 1 – Two K-class blimps of the United States Navy complete the first transatlantic crossing by non-rigid airships, from the U.S. to French Morocco, with two stops. June 2 – WWII: The Provisional Government of the French Republic is established. June 3 – Hans Asperger publishes his paper on Asperger syndrome. June 4 – WWII: Rome falls to the Allies, the first Axis capital to fall. A hunter-killer group of the United States Navy captures the , marking the first time a U.S. Navy vessel has captured an enemy vessel at sea since the War of 1812. Some significant intelligence data is acquired. June 5 – WWII: The German navy's Enigma messages are decoded in England almost in real time. British Group Captain James Stagg correctly forecasts a brief improvement in weather conditions over the English Channel, which will permit the following day's Normandy landings to take place (having been deferred from today due to unfavourable weather). At 10:15 p.m. local time, the BBC transmits coded messages including the second line of the Paul Verlaine poem "Chanson d'automne" to the French Resistance, indicating that the invasion of Europe is about to begin. More than 1,000 British bombers drop 5,000 tons of bombs on German gun batteries on the Normandy coast, in preparation for D-Day. US and British airborne divisions drop into Normandy, in preparation for D-Day. D-Day naval deceptions are launched. June 6 – WWII: D-Day: 155,000 Allied troops shipped from England land on the beaches of Normandy in northern France, beginning Operation Overlord and the Invasion of Normandy. The Allied soldiers quickly break through the Atlantic Wall and push inland, in the largest amphibious military operation in history. This operation helps liberate France from Germany, and also weakens the Nazi hold on Europe. June 7 – WWII: Bayeux is liberated by British troops. Operation Perch, a British attempt to capture Caen from the Germans, commences; it is abandoned on June 14. The steamer Danae (), carrying 600 Cretans (including 350 Greek Jews) on the first leg of the journey to Auschwitz, is sunk, with no known survivors, off Santorini. Joel Brand is intercepted by British agents in Aleppo. June 9 – WWII: Soviet leader Joseph Stalin launches the Vyborg–Petrozavodsk Offensive against Finland, with the intent of defeating Finland before pushing for Berlin. June 10 – WWII: Oradour-sur-Glane massacre: 642 men, women and children are killed in France. June 13 – WWII: Germany launches the first V-1 flying bomb attack on London. June 15 – WWII: Battle of Saipan: United States forces land on Saipan. June 15–16 – WWII: Bombing of Yawata – The United States Army Air Forces conduct the first air raid on the Japanese home islands. June 16 – At age 14, African-American teenage boy George Stinney Jr. becomes the youngest person ever executed by electric chair in the United States. June 17 – Iceland declares full independence from Denmark. June 19 – WWII: A severe storm badly damages the Mulberry harbours on the Normandy coast. June 20 – WWII: A V-2 rocket becomes the first man-made object to cross the Kármán line and reach the edge of space. June 22 – WWII: Operation Bagration: A general attack by Soviet forces clears the German forces from Belarus, resulting in the destruction of German Army Group Centre, possibly the greatest defeat of the Wehrmacht during WWII. Burma Campaign: The Battle of Kohima ends in a British victory. June 23 – The Holocaust: Maurice Rossel of the International Committee of the Red Cross visits Theresienstadt concentration camp, uncritically accepting the propaganda view of it presented by the Schutzstaffel. June 25 – WWII: Battle of Tali-Ihantala (the largest battle ever in the Nordic countries): Finland is able to resist the Soviet attack, and thus manages to remain an independent nation. Cherbourg is bombarded by ships of the United States Navy and British Royal Navy, in support of U.S. ground troops. June 26 – WWII: American troops enter Cherbourg. June 29 – WWII: American submarine torpedoes Japanese troop transport ; 5,400 drown. June 30 – WWII: American submarine torpedoes Japanese troop transport ; 3,219 drown.
thumb|Allied troops land on the beaches of Normandy during D-Day. thumb|LVTs heading for shore on June 15, 1944, during the Battle of Saipan. June 1 – Two K-class blimps of the United States Navy complete the first transatlantic crossing by non-rigid airships, from the U.S. to French Morocco, with two stops. June 2 – WWII: The Provisional Government of the French Republic is established. June 3 – Hans Asperger publishes his paper on Asperger syndrome. June 4 – WWII: Rome falls to the Allies, the first Axis capital to fall. A hunter-killer group of the United States Navy captures the , marking the first time a U.S. Navy vessel has captured an enemy vessel at sea since the War of 1812. Some significant intelligence data is acquired. June 5 – WWII: The German navy's Enigma messages are decoded in England almost in real time. British Group Captain James Stagg correctly forecasts a brief improvement in weather conditions over the English Channel, which will permit the following day's Normandy landings to take place (having been deferred from today due to unfavourable weather). At 10:15 p.m. local time, the BBC transmits coded messages including the second line of the Paul Verlaine poem "Chanson d'automne" to the French Resistance, indicating that the invasion of Europe is about to begin. More than 1,000 British bombers drop 5,000 tons of bombs on German gun batteries on the Normandy coast, in preparation for D-Day. US and British airborne divisions drop into Normandy, in preparation for D-Day. D-Day naval deceptions are launched. June 6 – WWII: D-Day: 155,000 Allied troops shipped from England land on the beaches of Normandy in northern France, beginning Operation Overlord and the Invasion of Normandy. The Allied soldiers quickly break through the Atlantic Wall and push inland, in the largest amphibious military operation in history. This operation helps liberate France from Germany, and also weakens the Nazi hold on Europe. June 7 – WWII: Bayeux is liberated by British troops. Operation Perch, a British attempt to capture Caen from the Germans, commences; it is abandoned on June 14. The steamer Danae (), carrying 600 Cretans (including 350 Greek Jews) on the first leg of the journey to Auschwitz, is sunk, with no known survivors, off Santorini. Joel Brand is intercepted by British agents in Aleppo. June 9 – WWII: Soviet leader Joseph Stalin launches the Vyborg–Petrozavodsk Offensive against Finland, with the intent of defeating Finland before pushing for Berlin. June 10 – WWII: Oradour-sur-Glane massacre: 642 men, women and children are killed in France. June 13 – WWII: Germany launches the first V-1 flying bomb attack on London. June 15 – WWII: Battle of Saipan: United States forces land on Saipan. June 15–16 – WWII: Bombing of Yawata – The United States Army Air Forces conduct the first air raid on the Japanese home islands. June 16 – At age 14, African-American teenage boy George Stinney Jr. becomes the youngest person ever executed by electric chair in the United States. June 17 – Iceland declares full independence from Denmark. June 19 – WWII: A severe storm badly damages the Mulberry harbours on the Normandy coast. June 20 – WWII: A V-2 rocket becomes the first man-made object to cross the Kármán line and reach the edge of space. June 22 – WWII: Operation Bagration: A general attack by Soviet forces clears the German forces from Belarus, resulting in the destruction of German Army Group Centre, possibly the greatest defeat of the Wehrmacht during WWII. Burma Campaign: The Battle of Kohima ends in a British victory. June 23 – The Holocaust: Maurice Rossel of the International Committee of the Red Cross visits Theresienstadt concentration camp, uncritically accepting the propaganda view of it presented by the Schutzstaffel. June 25 – WWII: Battle of Tali-Ihantala (the largest battle ever in the Nordic countries): Finland is able to resist the Soviet attack, and thus manages to remain an independent nation. Cherbourg is bombarded by ships of the United States Navy and British Royal Navy, in support of U.S. ground troops. June 26 – WWII: American troops enter Cherbourg. June 29 – WWII: American submarine torpedoes Japanese troop transport ; 5,400 drown. June 30 – WWII: American submarine torpedoes Japanese troop transport ; 3,219 drown.