The 'Battle of Pszczyna' was a series of engagements between German and Polish forces near the town of Pszczyna during the first days of the 'Weiss' (i) invasion of Poland (1/2 September 1939).
The 'Battle of Pszczyna' formed part of the 'Battle of the Polish Border', and was characterised by an initial Polish success on on 1 September and then a crushing Polish defeat on 2 September near Ćwiklice as a result of a major tactical error by the Polish high command, resulting in premature withdrawal of Generał brygady Antoni Szylling’s entire Armia 'Kraków' from Upper Silesia.
The battle was fought along a part of the Polish defence belt 12.5 miles (20 km) wide and 43.5 miles (70 km) between the Polish/German border in the west and the Przemsza and Soła rivers in the east. The Rybnicki and Kobiorski forests constituted the northern edge of the battlefield, and to the south the Vistula river, together with the Odra and Piotrówka rivers provided natural protection for tthe Polish forces. The defensive line, 13.67 miles (22 km) long, had been constructed between 1929 and 1933 as part of the strategic plan to secure the national border around Poland’s central industrial region. The fortifications included concrete shelters manned by Generał brygady Jan Jagmin-Sadowski’s (later Pułkownik Wladyslaw Powierza’s) 23rd Division. In 1936/37 two new bridges were built over the Vistula and Chochułka rivers near Goczałkowice and Pszczyna for military transport, and the supply roads were paved with asphalt in late 1930s. In overall terms, the defence line seemed sufficient, by the standards of the day, to stop an armoured attack. The tactical mistake of the Polish command was the assumption that the attack of Generalleutnant Heinrich von Vietinghoff-Scheel’s 5th Panzerdivision, a formation of General Ernst Busch’s VIII Corps of General Wilhelm List’s 14th Army within Generaloberst Gerd von Rundstedt’s Heeresgruppe 'Süd', would require the support of infantry to secure its rear.
The battle was fought in four phases: firstly, on 1 September, the successful Polish defense of the outer positions near the villages of Brzeźce and Wisła Wielka; secondly, in the morning of 2 September, the Polish defence of the main positions near Pszczyna; thirdly, in the afternoon of 2 September, battles near Ćwiklice; and fourthly, on 3/4 September, the Polish success in breaking off the engagement and withdrawing. This all cost the Poles heavy casualties as the their withdrawal was successful mainly as a result of a diversionary counterattack on Ćwiklice by two battalions of the 16th Regiment, which bought the time needed for other units to regroup and pull back.
During the battle’s second day, therefore, the Polish forces suffered a defeat and were forced to retreat. The primary reason of the Polish reverse, other than the German forces' great numerical and matériel superiorities, lay in the fact that the Polish commanders incorrectly predicted the direction of the main German attack on 2 September. As the result, the whole Polish defence plan failed as it had become impossible to activate the great 'big bag' trap which had been schemed for the German armour. This was weak in its centre but strong on its flanks front, and with powerful artillery to aid in attacking the German forces which entered the 'bag' through its weak centre. Moreover, a Polish excess of confidence, after successes of the previous day (especially the fierce, but short, success near the village of Brzeźce, also contributed to the Polish defeat.
Because of their over-confidence, Polish commanders decided to make the 'big-bag' trap less deep, which meant that it was less flexible, and Polish positions would therefore be easier to crush if the defence was not successful, as in fact eventuated, but if on the other hand the defence proved successful, which did not happen as a result of the unexpected strength and axis of the German main attack, the shallow 'big bag' trap would be more effective because the Germans would be stopped more quickly and with greater casualties as a result of the Polish forces' greater concentration of firepower.
The defeat at Pszczyna, which cost a high percentage of losses in divisional artillery, compelled the Polish high command to pull back the entire front line and thus yield Upper Silesia to the Germans.