The Battle of Mława was fought from 1 to 3 September 19392, in the first days of the German invasion of Poland. North of the town of Mława, the Polish 20th Infantry Division under Colonel Wilhelm Liszka-Lawicz, part of General Emil Krukowicz-Przedrzymirski's Modlin Army, defended a line of concrete bunkers and anti-tank obstacles built that summer. It threw back repeated German attacks, including an armoured assault at Uniszki Zawadzkie, but when German forces outflanked the position to the east, the defenders were ordered to withdraw on the night of 3 to 4 September.
On the morning of 1 September 1939 the German 3rd Army struck south from East Prussia toward Warsaw3. Across its path, in fields north of the small town of Mława, Polish soldiers waited in bunkers that had been poured only weeks before.
The road to Warsaw
The border with East Prussia lay little more than 100 km north of Warsaw. Defending it was the task of the Modlin Army of General Emil Krukowicz-Przedrzymirski, which faced the German 3rd Army of General Georg von Küchler, advancing on the capital from the north.
Bunkers built in haste
In the summer of 1939 the Poles fortified the high ground north of Mława with concrete shelters, trenches and anti-tank ditches. The position was held by the 20th Infantry Division of Colonel Wilhelm Liszka-Lawicz, with the Mazovian Cavalry Brigade covering its eastern flank4.
Panzers at Uniszki Zawadzkie
On 1 September German infantry attacked the bunkers around Mława and were thrown back. Near Uniszki Zawadzkie, on the road from East Prussia, the Kempf Panzer Division ran into an anti-tank ditch5 and Polish fire and lost a number of tanks; the attack failed. Renewed German assaults the next day were held around Mława, but on the eastern wing at Rzęgnowo the 79th Infantry Regiment was outflanked and fell back4.
Outflanked
Unable to break through head on, the Germans pushed round the eastern end of the line, where the cavalry and weaker forces could not stop them. A Polish counterattack by the 8th Infantry Division failed amid confusion4, and with the position threatened from the flank and rear, the defenders were ordered to withdraw on the night of 3 to 4 September. The retreat toward the Vistula cost the Poles heavily.
Why Mława matters
Mława showed that well-prepared Polish troops in fortified positions could stop German infantry and armour in the opening days of the war, and it held up the 3rd Army's advance on Warsaw for three days6. Together with Westerplatte, Mokra and Wizna, it is remembered as one of the stubborn first battles of September 1939. Several of its bunkers survive and can still be visited.1