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WWII On This Day: September 20

What happened on September 20 during World War II? This date brings together 6 events from 1939, 1941 and 1944, with period photographs and links to the full operations documented across WW2 Theatres.

1939
The German battleship Schleswig-Holstein firing on the Polish depot at Westerplatte, September 1939.
Schleswig-Holstein firing on Westerplatte, 1 September 1939 · Public domain · Source
Invasion of Poland 1939

Political killing begins behind the German advance

Einsatzgruppen, police, Selbstschutz and Wehrmacht units carried out arrests, hostage shootings and executions during the campaign. Members of the intelligentsia, clergy, political leadership and other people classified as potential organisers of resistance were particular targets. Operation Tannenberg had been prepared before the invasion. IPN material on the later Intelligenzaktion records about twenty thousand people killed during the September campaign among categories treated by German authorities as enemies of the Reich, with further mass killing expanding under occupation. Military conquest and the destruction of Polish political and social leadership developed together…

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1941
A German infantryman beside a burning Soviet BT-7 tank and a dead Soviet soldier, June 1941.
Bundesarchiv Bild 101I-020-1268-36 · CC BY-SA 3.0 DE · Source
Operation Barbarossa

Kirponos is killed during the attempted breakout

Southwestern Front headquarters attempted to escape east in small groups as the pocket fragmented. Mikhail Kirponos, who had commanded the front from the frontier battles through the Kyiv crisis, was killed during the breakout on 20 September. By then the front-level command system was disintegrating. Armies and headquarters were separated, radio links failed, and local commanders increasingly acted on their own information and immediate circumstances. Kirponos had warned of the encirclement before the German pincers met. His death during the escape marked the collapse of the headquarters that had directed…

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1944
Allied transport aircraft and gliders overhead while paratroops descend over the Netherlands during Operation Market Garden on 17 September 1944.
U.S. Army Air Forces / National Archives, NAID 531308 · Public domain in the United States · Source
Operation Market Garden

The Waal crossing

The 3rd Battalion, 504th Parachute Infantry Regiment crossed the Waal a mile downstream of the bridge in twenty-six canvas assault boats, in daylight, against a defended far bank, under smoke that blew clear. About half the boats survived the first trip. The men who reached the north bank cleared the far end of the rail and road bridges from behind.

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Carriers and lorries crossing the bridge at Nijmegen, 21 September 1944. In the foreground is the body of a German soldier.
Carriers and lorries crossing the bridge at Nijmegen, 21 September 1944. In the foreground is the body of a German soldier. Imperial War Museums, B 10175 · Public domain Source
Operation Market Garden

Nijmegen bridge taken intact

After the Waal crossing opened the north bank, Grenadier Guards tanks moved onto the Nijmegen road bridge while American paratroopers pressed in from the far side. German demolition charges had been prepared but the span remained intact. By evening Allied armour held the crossing. Arnhem was still about eleven miles farther north, with German forces between Nijmegen and the surviving British positions.

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Operation Market Garden

The bridge force is overrun

Frost's men had held the northern ramp for about eighty hours against tanks, assault guns and mortars, in buildings burning around them, with no resupply and no water. Ammunition ran out. Frost was wounded and taken prisoner with the rest. German engineers cleared the bridge overnight and 10th SS armour was over it and heading south by the morning.

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Warsaw Uprising: Two medics and a soldier (right) from "Parasol" battalion after coming out of sewers at Warecka Street near Nowy Świat (North Śródmieście district). In the center Maria Stypułkowska-Chojecka "Kama". On the right Krzysztof Palester "Krzych".
Warsaw Uprising - Soldiers from Parasol on Warecka Street 1 September 1944 · Jerzy Chrzanowski · Public domain · Source
The Warsaw Rising

The bridgehead is divided

German attacks split the Czerniaków defence into smaller positions along the river and around Wilanowska Street. Evacuation by boat and sewer became increasingly difficult. Some Home Army troops withdrew toward Mokotów, while Polish 1st Army soldiers and remaining insurgents continued to hold isolated buildings near the bank.

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