The Battle of Mlawa

At noon on September 1, 1939 the Polish line of defense manned by the 20th Infantry Division was attacked by the 1st Army Corps under General Walter Petzel. Although the attacking forces were equipped with tanks and supported by warplanes, the initial assault was repelled by Polish-made 37mm Armata ppanc. wz. 36 anti-tank guns. Georg von Küchler, the commander of German Third Army, ordered his units to attack the Polish forces several times in a row, but all attacks were broken and in the late evening the Germans were forced to withdraw to their initial positions.

The following afternoon the German units started heavy artillery bombardment of the Rzegnów position on the right flank of the Polish forces. After two hours of constant artillery fire, the assault was started and, in the result of close combat, the Polish defenders started to waver. The counterattack of the Polish 79th Infantry Regiment was unsuccessful and the commander of the Polish Modlin Army ordered the 20th Division to extend further eastwards and prepare the defence of its right flank between the villages of Dębsk and Nosarzewo. At the same time the 8th Infantry Division, until then held in reserve near Ciechanów, was ordered to prepare a counterattack.

The 8th Division arrived in the area in the early hours of September 3. As the Mazovian Cavalry Brigade operating further eastwards was also endangered by German armoured troops, the army commander ordered the division to split its forces and attack in two directions: towards Grudusk east of Mława and towards Przasnysz. However, conflicting orders and German diversants operating in the rear disrupted both attacks and led to chaos in the Polish ranks. In the evening the division was mostly destroyed and only the 21st Infantry Regiment of Colonel (later General) Stanisław Sosabowski managed to withdraw from the fights towards the Modlin Fortress. Despite this, the German attacks towards both flanks of the 20th Infantry Division were unsuccessful.

On September 3 the German engineers finally managed to cut through Polish antitank barriers. The Germans used the local civilians as human shields, which allowed them to finally capture several bunkers on the left flank of the Polish forces, but were unable to push forwards. On the right flank, in the Rzegnów section of the front to the east of the swamps, the attacks were more successful and in the late evening elements of German Wodrig Corps finally broke through the lines of the 79th Infantry Regiment to the rear of the Poles. This widened the front gap in the area of Grudusk.

General Emil Krukowicz-Przedrzymirski, facing the risk of his forces being outflanked and surrounded, ordered the 20th division and the remnants of the 8th to withdraw towards Warsaw and Modlin, finally abandoning the fortified positions.

After the Battle

The withdrawal was started in the early morning of September 4. Although the German mechanized units suffered heavy losses and were unable to maintain pursuit, the area to the south of Mława was very lightly forested and the Polish forces were constantly bombarded and strafed by the German Luftwaffe, suffering heavy losses both in troops and equipment.

Although the position was abandoned, the German forces suffered substantial losses and it was not until September 13, when they finally managed to reach the Modlin Fortress, located less than 100 kilometres to the south.

Opposing forces

Poland

Germany