<P> Although the Polish military had prepared for conflict, the civilian population remained largely unprepared . Polish pre-war propaganda emphasized that any German invasion would be easily repelled . Consequently, Polish defeats during the German invasion came as a shock to the civilian population . Lacking training for such a disaster, the civilian population panicked and retreated east, spreading chaos, lowering troop morale and making road transportation for Polish troops very difficult . </P> <P> Following several German - staged incidents (like the Gleiwitz incident, a part of Operation Himmler), which German propaganda used as a pretext to claim that German forces were acting in self - defence, the first regular act of war took place on 1 September 1939, at 04: 40, when the Luftwaffe attacked the Polish town of Wieluń, destroying 75% of the city and killing close to 1,200 people, most of them civilians . Five minutes later, the old German pre-dreadnought battleship Schleswig - Holstein opened fire on the Polish military transit depot at Westerplatte in the Free City of Danzig on the Baltic Sea . At 08: 00, German troops--still without a formal declaration of war issued--attacked near the Polish village of Mokra . The Battle of the Border had begun . Later that day, the Germans attacked on Poland's western, southern and northern borders, while German aircraft began raids on Polish cities . The main axis of attack led eastwards from Germany through the western Polish border . Supporting attacks came from East Prussia in the north, and a joint German - Slovak tertiary attack by units (Field Army "Bernolák") from the German - allied Slovak Republic in the south . All three assaults converged on the Polish capital of Warsaw . </P> <P> France and the UK declared war on Germany on 3 September, but failed to provide any meaningful support . The German - French border saw only a few minor skirmishes, although the majority of German forces, including 85% of their armoured forces, were engaged in Poland . Despite some Polish successes in minor border battles, German technical, operational and numerical superiority forced the Polish armies to retreat from the borders towards Warsaw and Lwów . The Luftwaffe gained air superiority early in the campaign . By destroying communications, the Luftwaffe increased the pace of the advance which overran Polish airstrips and early warning sites, causing logistical problems for the Poles . Many Polish Air Force units ran low on supplies, 98 of their number withdrew into then - neutral Romania . The Polish initial strength of 400 was reduced to just 54 by 14 September and air opposition virtually ceased . </P> <P> By 3 September, when Günther von Kluge in the north had reached the Vistula River (some 10 km (6.2 mi) from the German border at that time) and Georg von Küchler was approaching the Narew River, Walther von Reichenau's armor was already beyond the Warta river; two days later, his left wing was well to the rear of Łódź and his right wing at the town of Kielce . On 7 September the defenders of the Polish capital had fallen back to a 48 km (30 mi) line paralleling the Vistula River where they rallied against German tank thrusts . The defensive line ran between Płońsk and Pułtusk, northwest and northeast of Warsaw, respectively . The right wing of the Poles had been hammered back from Ciechanów about 40 km (25 mi) northwest of Pułtusk pivoting on Płońsk . At one stage in the struggle the Poles were driven from Pułtusk and the Germans threatened to turn the Polish flank and thrust on to the Vistula and Warsaw . Pułtusk, however, was regained in the face of withering German fire . A considerable number of German tanks were captured after a German attack had pierced the line but the Polish defenders outflanked them . By 8 September, one of Reichenau's armored corps--having advanced 225 km (140 mi) in the first week of the campaign--reached the outskirts of Warsaw . Light divisions on Reichenau's right were on the Vistula between Warsaw and the town of Sandomierz by 9 September while List--in the south--was on the San River north and south of the town of Przemyśl . At the same time, Guderian led his 3rd Army tanks across the Narew, attacking the line of the Bug River, already encircling Warsaw . All the German armies made progress in fulfilling their parts of the Fall Weiss plan . The Polish armies were splitting up into uncoordinated fragments, some of which were retreating while others were launching disjointed attacks on the nearest German columns . </P>

Country that with england declared war on germany after the german invasion of poland