USA: In experimental attacks on ships, the battleship OSTFRIESLAND is sunk in Chesapeake Bay, Maryland, proving that capital ships can be destroyed by unopposed aircraft.
1936 — , July 21
Spain: Day 5 of 985 of the Spanish Civil War. El Ferrol, the main naval base in northwest Spain, surrenders to the Nationalists. As a result the Nationalists acquire several warships.
1937 — , July 21
Spain: Day 370 of 985 of the Spanish Civil War.
CBI - China: Day 15 of 2,987 of the 2nd Sino-Japanese War.
Day 15 of 33 of the 2nd Battle of Hebei.
Day 8 of 22 of the Battle of Tainjin-Beijing.
1938 — , July 21
Germany: Newly passed laws require all Jews to carry identification cards, effective 01 Jan 1939.
Spain: Day 735 of 985 of the Spanish Civil War.
CBI - China: Day 380 of 2,987 of the 2nd Sino-Japanese War.
Day 41 of 139 of the Battle of Wuhan.
1939 — , July 21
Germany: Adolf Eichmann is appointed director of the Prague Office of Jewish Emigration.
CBI - China: Day 745 of 2,987 of the 2nd Sino-Japanese War.
Day 38 of 68 of the Battle of Tianjin.
CBI - Mongolia: Day 72 of 129 of the Battle of Khalkhin Gol, a border dispute between the Soviet Union and Japan.
1940 — , July 21
Atlantic: German sub U-30 sinks the British ship ELLAROY 180 miles west of Cape Finisterre, Spain.
ETO - UK: Day 12 of 114 of the Battle of Britain. The Luftwaffe draws the RAF into a nasty air battle over the Channel.
ETO - Germany: The RAF bombs Hamm, Kassel and Soest.
East Africa: Day 42 of 537 of Italy's East African campaign in the lands south of Egypt.
CBI - China: Day 1,111 of 2,987 of the 2nd Sino-Japanese War.
Day 250 of 381 of the Battle of South Guangxi.
1941 — , July 21
USA: Roosevelt asks the United States Congress to modify the Selective Service Act, increasing the period of active service and including another 30 months in reserve.
South America: Day 17 of 27 of the Ecuadorian-Peruvian War, a territorial dispute between Peru and Ecuador.
Germany: The Majdanek Concentration Camp near Lublin, Poland, becomes operational.
Russian Front - Finland: Day 23 of 142 of Operation SILVER FOX, a joint German-Finnish campaign to capture the Russian port of Murmansk in the Arctic.
Russian Front - Finland: Day 21 of 140 of Operation ARCTIC FOX, a joint German-Finnish campaign against Soviet Northern Front defenses at Salla, Finland.
Russian Front - Finland: Day 30 of 164 of the Battle of Hanko. German sub U-140 sinks the Soviet sub M-94 in the Baltic Sea.
Russian Front - Finland: Day 12 of 18 of Finland's reconquest of Ladoga, Karelia. The Finns continue their offensive on Lake Ladoga northeast of Leningrad.
Russian Front: Day 30 of 167 of Germany's Operation BARBAROSSA, the invasion of the USSR.
Russian Front - North: Heavy fighting between German and Soviet troops continues near Lake Peipus outside Leningrad.
Russian Front - Center: Outside of Minsk, German SS troops order 30 Byelorussians to bury 45 alive Jews in a pit. Upon refusal, the SS executes the entire group of 75 by machine gun fire.
Russian Front - Center: Day 16 of 31 of the 1st Battle of Smolensk, Russia. From a base near Smolensk, the Luftwaffe makes several bombing attacks on Moscow.
Russian Front - Center: Day 9 of 12 of the Battle of Zhlobin, Belarus.
Russian Front - South: Day 7 of 25 of the Battle of Uman, Ukraine.
Russian Front - South: Day 20 of 21 of the Battle of Bessarabia, Russia. German and Romanian troops continue their attack at Bessarabia to take the land and city that Romania was forced to cede to the USSR a year ago.
Russian Front - South: German and Romanian troops keep pushing toward Vinnitsa and the Black Sea port of Odessa, Ukraine.
MTO - Egypt: Charles de Gaulle meets with the British Minister of State in Cairo to complain of the arrangements for the Middle East where the Free French troops are placed under British command.
MTO - Libya: Day 103 of 256 of the Siege of Tobruk.
East Africa: Day 407 of 537 of Italy's East African campaign in the lands south of Egypt.
CBI - China: Day 1,476 of 2,987 of the 2nd Sino-Japanese War.
1942 — , July 21
Atlantic: German sub U-160 sinks the transport DONOVANIA off Grand Matelot Point, Trinidad.
Russian Front - North: Day 317 of 872 of the Siege of Leningrad.
Russian Front - North: Day 78 of 658 of the Siege of the Kholm Pocket.
Russian Front - Center: Day 20 of 22 of Germany's Operation SEYDLITZ, a plan to trap and capture numerous Soviet troops.
Russian Front - South: Day 24 of 27 of the Battle of Voronezh, Russia.
Russian Front - South: Day 24 of 150 of Germany's CASE BLUE, the failed offensive to take the Caucasus oil fields.
MTO - Greece: US B-24s attacks targets at Suda Bay.
MTO - Egypt: Day 21 of 27 of the 1st Battle of El Alamein. New Zealand troops gain key positions but without tank support they are extremely vulnerable to a counter-attack.
East Africa: Day 78 of 186 of the Battle of Madagascar.
CBI - China: Day 1,841 of 2,987 of the 2nd Sino-Japanese War.
Day 68 of 124 of Japan's Zhejiang-Jiangxi Campaign, launched to punish anyone suspected of aiding the Doolittle raiders in China. Roughly 250,000 Chinese will be killed.
PTO - Alaska: Day 45 of 435 of the Battle of Kiska, Aleutian Islands. US submarines sink three Japanese destroyers near Kiska.
PTO - Malaya: Day 153 of 357 of the Battle of Timor Island.
PTO - New Guinea: Day 1 of 119 of the Battle of the Kokoda Track. The Allies need this important trail cutting across the island from Buna to Port Moresby. The Japanese already hold three key spots on the north beaches and tonight they will land additional troops near Buna. The US 5th Air Force attacks the Japanese convoy with the invasion force.
1943 — , July 21
Atlantic: A Navy PBY-5A Catalina sinks German sub U-662 in the estuary of the Amazon River in Brazil.
Russian Front - North: Day 682 of 872 of the Siege of Leningrad.
Russian Front - North: Day 443 of 658 of the Siege of the Kholm Pocket.
Russian Front - Center: Day 17 of 50 of the Battle of Kursk, Russia.
Russian Front - Center: Day 10 of 38 of the Battle of Orel, Russia.
Russian Front - South: Day 9 of 48 of the USSR's Lvov-Sandomierz Offensive. The surrounded German troops at Brody keep trying to fight their way out but are stuck.
MTO - Yugoslavia: The German authorities in Belgrade offer a massive reward for the betrayal and capture of the Yugoslav partisan leader Josef Tito.
MTO - Italy: Day 13 of 40 of the Battle of Sicily. RAF and US Air Forces provide air support. US troops capture Alimena, Corleone, Valledolmo, San Margheritaa and Castelvetrano while the Canadians capture Leonforte.
CBI - China: Day 2,206 of 2,987 of the 2nd Sino-Japanese War.
PTO - Alaska: Day 410 of 435 of the Battle of Kiska, Aleutian Islands. US 11th Air Force bombs targets on Kiska Island while two US Navy destroyers bombard the Gertrude Cove area.
PTO - Gilbert Islands: Japanese bombers attack the US airfield at Funafuti.
PTO - New Guinea: Day 91 of 148 of the 2nd Battle of Lae-Salamaua. US 5th and 13th Air Forces provide air support.
PTO - Solomon Islands: Day 32 of 67 of the Battle of New Georgia. US 5th and 13th Air Forces provide air support.
1944 — , July 21
Germany: German Lieutenant Colonel Claus von Stauffenberg is executed in Berlin, along with three others, in the aftermath of yesterday's failed bomb plot to kill Adolf Hitler and to overthrow the Nazi government.
Lt Col Claus von Stauffenberg at left (Rastenburg, 15 Jul 44)
The 20 Jul 44 plot was the culmination of the efforts of several groups in the German Resistance to overthrow the Nazi-led German government. For his involvement in the movement he was shot shortly after the failed attempt.
Describing her late husband, Nina von Stauffenberg said, "He let things come to him, and then he made up his mind ... one of his characteristics was that he really enjoyed playing the devil's advocate. Conservatives were convinced that he was a ferocious Nazi, and ferocious Nazis were convinced he was an unreconstructed conservative. He was neither."
Atlantic: British frigates HMS CURZON and HMS EKINS sink the German sub U-212 south of Brighton, England.
Atlantic: The Brazilian corvette CAMAQUA is capsized by a series of huge waves and sinks 27 miles off Recife, Brazil.
ETO - UK: Day 39 of 86 of the V-1 "Buzz Bomb" offensive on Britain.
ETO - France: Day 46 of 49 of Operation OVERLORD, the Allied invasion of Normandy, France, known forever simply as D-Day. D-Day+45: Allied Air Forces provide air support. A second day of heavy rain put a halt to all ground operations.
ETO - France: Day 46 of 62 of the Battle of Caen.
ETO - Germany: US 8th Air Force bomb various targets throughout Germany.
Russian Front: The USSR announces that a separate Soviet-sponsored government is to be set up to administer areas of liberated Poland, angering the Polish government-in-exile based in Britain.
Russian Front - Finland: Day 31 of 50 of the Battle of Karelia. Soviet troops continue their offensive against the Finns in eastern Karelia between Lake Ladoga and Lake Onega in northern Russia.
Russian Front - North: Day 171 of 191 of the Battle of the Narva Isthmus, Estonia. Both German and Soviet troops remain locked in their defensive positions.
Russian Front - Center: Day 17 of 27 of the Battle of Siauliai, Lithuania. The Soviets capture Ostrov, Russia.
Russian Front - Center: Day 17 of 23 of the Battle of Belostock, Poland.
Russian Front - Center: Day 9 of 15 of the Battle of Lvov, Poland. Some of the German troops trapped inside the Brody Pocket manage to break out and reach German lines.
Russian Front - Center: Day 9 of 15 of the Battle of Stanislav, Poland.
Russian Front - Center: Day 4 of 16 of the Battle of Lublin, Poland.
MTO - Czechoslovakia: US 15th Air Force: B-17 and B-24 bomb at Brüx (Czech word for "most").
MTO - Italy: The US 5th Army continues pushing to Pisa.
CBI - Burma: Day 139 of 166 of the UK's Operation THURSDAY. US 10th Air Force provides air support.
CBI - Burma: Day 134 of 147 of the Battle of Myitkyina. US 10th Air Force provides air support.
CBI - Burma: Day 112 of 302 of the Chinese Salween Offensive. US 14th Air Force provides air support.
CBI - China: Day 2,572 of 2,987 of the 2nd Sino-Japanese War.
Day 96 of 259 of Japan's Operation ICHI-GO.
Day 30 of 48 of the Battle of Hengyang. US 14th Air Force provides air support.
PTO - Caroline Islands: US 7th Air Force B-25s bomb targets in the Truk Atoll.
PTO - Dutch New Guinea: Day 20 of 61 of the Battle of Noemfoor. Although the island has been declared secured, bitter fighting from Japanese continues.
PTO - Mariana Islands: Day 1 of 21 of the 2nd Battle of Guam. US Army and Marines go ashore and quickly establish themselves a mile inland on this US territory that had fallen in the 3-day 1st Battle of Guam.
US officers plant flag eight minutes after troops begin landing on Guam
Guam is the largest of the Marianas, 32 miles long and 10 miles wide. It had been a United States possession since its capture from Spain in 1898 until it was captured by Japan on 10 Dec 41, following the attack on Pearl Harbor. By 1944 it had a large Japanese garrison.
The Japanese had learned from previous American assaults not to subject their men to the massive air and naval bombardments that would precede the invasion. Therefore their beach fortifications on Guam were sparsely manned, opting instead to heavily dig themselves in further inland.
Although the 2nd Battle of Guam will be declared over in 21 days (10 Aug 44), some 7,500 Japanese soldiers will remain at large in the jungles and will continue fighting with unorganized guerrilla tactics for some time to come.