The Battle of Bzura was the largest battle of the 1939 German invasion of Poland. The Polish Poznan Army under the command of General Tadeusz Kutrzeba launched a counterattack on the German 8th Army under the command of General Johannes Blaskowitz. Kutrzeba noticed that German troops were thinly spread out over a 30 kilometer defensive line, as the remainder of their troops were on their way to Warsaw. The Polish attack resulted in heavy losses for the German troops. About 1,500 German soldiers were killed or wounded and 3,000 taken prisoners. The coordinated threat of the Polish cavalry brigade, and accompanying TKS and TK-3 reconnaissance tanks threatened the flanks and rear of the advancing German units. As a result the Germans were pushed back by about 20 kilometres and the Polish army recaptured many towns. But by September 18 the Polish forces were at risk of being encircled. Germans continued their advance along both banks of the Bzura, launching heavy artillery fire, and supported by more than 300 aircraft. With their howitzers they shelled Polish positions for the next two days, from their vantage point on the Vistula's right bank. The battle came to an end on September 19, when several attempts by Polish forces to breakout had failed. The Germans outflanked the Polish army and seized all of western Poland.
The Battle of Hel began began as soon as the German armies had forced the Polish Armia Pomorze to retreat from the Danzig Corridor. The Hel peninsula was the only pocket of Polish resistance in northern Poland that continued to fight against the Nazi Germans. The Poles had already been defeated in the Battle of Tuchola Forest, the Battle of Westerplatte,the Battle of Gdynia and the Battle of Kępa Oksywska, among many other border battles. On September 3, Polish fighters succeeded in damaging a German destroyer but lost the ORP Gryf, a minelayer. The ensuing days resulted in attacks and counterattacks on both sides. On September 14, after the Luftwaffe attacked and sunk several Polish ships, the remainder of the Polish naval units joined the ground forces. The Baltic area came under German control. Though Polish troops were able to fire upon the Schleswig Holstein, it had little effect on the German destroyer. But the Poles successfully shot down from 46 to 53 German aircraft during the Battle. The Germans had cut Polish forces from the mainland and brought in heavy artillery batteries and an armored train battery to support a continuous assault on the Poles. Despite the overpowering fire power, the Germans could only advance slowly as the Poles fiercely counterattacked. By October 1 the Polish outpost was very low on supplies and ammunition, and without Allied relief or support, the only viable option was to capitulate.
The Blitz Continued. The Germans attempted to force Britain to surrender by a round the clock, all-out bombing campaign against the city of London and by attacking Britain's vital sea communications. Due to the poor weather, the Germans raids focused mainly on the London suburbs and the airfield at Farnborough. The next day German attacks resumed which resulted in the loss of 24 aircraft, including 13 Bf 109s. The RAF lost 17 fighters and six pilots. The next German onslaught had to be postponed due to inclement weather and they resumed attacks on September 15, 1940.