Defending the border

After the carnage and destruction of the First World War finally came to an end in 1918, the defeated German and Austro-Hungary empires were carved up leading to the creation of new countries (the Polish Second Republic being one of them).

This new state found itself next to German, with its border only 120 km from the Polish capital, Warsaw.

By the 1930’s, as the growing menace from Nazi German became apparent, the Poles established a main defensive force – the Modlin Army (Led by Brigadier General Emil Krukowicz-Przedrzymirski) – to guard this border and prevent any attacking force from threatening Warsaw. The Polish defences in this area had been strengthened with concrete bunkers and field fortifications.

Colonel Wilhelm Lawicz-Liszka, Commander of the Polish 20th Infantry Division.


General Władysław Anders, Commander of the Nowogródzka Cavalry Brigade.

Colonel Jan Karcz, Commander, Mazowiecka Cavalry Brigade.


The defence line

Current map showing location of Mława in Poland.

The Polish defence line was situated along the Narew and Vistula rivers, the Poles taking advantage of these natural barriers.

The Modlin army were moved here to man the defences in case of a German attack.

There were already several 19th century fortifications in this location which were implemented into the defence line but the plains area to the north of it remained vulnerable, due to the flat, low-lying land being ideal tank movement.

Iron railway tracks (on the right of the photo) were used as an effective defence against German armour.

Polish anti-tank barriers at Mława,

In the event of a German breakthrough, the Polish forces – under the command of General Przedrzymirski-Krukowicz – would withdraw south to the Narew and Vistula rivers and mount a defence in conjunction with the Narew Independent Operation Group, commanded by General Czesław Młot-Fijałkowski, which would guard the Modlin army’s flanks.

Polish bunker built by Narew Independent Operational Group at Mława.


With the increase of tensions between Poland and Germany, in March 1939, the Polish 20th Infantry Division was sent to reinforce the Modlin army. Several trainloads of concrete were used to construct additional fortifications and a mixture of soldiers, combat engineers from the 20th engineering battalion (commanded by Major. Juliusz Levittoux) and civilian volunteers all worked on the fortifications. By July/August much had been completed but at the outbreak of war, not all the bunkers were completed.

Prior to the outbreak of war on 1st September 1939, the Polish Modlin army consisted of:

  • 20th Infantry Division
  • 8th Infantry Division
  • Nowogródzka Cavalry Brigade
  • Mazowiecka Cavalry Brigade

Polish fort at Mława. The Poles reinforced their defence in this area extensively in the lead up to the German invasion of Poland on 1st September, 1939.

Aerial view of part of the Mława fortifications.

German forces

The Germans 3rd Army was given the task of breaking the Polish line and was commanded by the experienced General Georg von Küchler, who had served in the German military in the First World War and during the Interwar period.

General Georg von Küchler, Commander German 3rd Army.

General Walter Petzel, Commander German 1st Army Corps.

General Albert Wodrig, Commander German 'Wodrig' Army Corps.

His forces were split into two groups:

1st Army Corps (Commanded by General Walter Petzel)

  • Panzer Division Kempf
  • 61st Infantry Division
  • 11th Infantry Division

"Wodrig" Army Corps (Commanded by General Albert Wodrig)

  • 1st Infantry Division
  • 12th Infantry Division
  • 1st Cavalry Brigade

The Battle

Map detailing the actions at Mława.

At midday on 1 September 1939, the day Germany embarked on the invasion of Poland, the Polish Infantry Division found itself under attack by the German 1st Army Corps.

Despite the Germans using armour and Luftwaffe air support, the Poles managed to hold against the onslaught, their 37mm Armata ppanc. wz. 36 anti-tank guns proving their worth against the German tanks.

Despite this initial failure, the German Third army commander Küchler pressed General Petzel’s 1st Army Corp to keep up the pressure and several more attacks were launched against the stubborn Poles, but each one was beaten back, and the Germans were forced to withdraw to their original starting positions.

German Panzer I tank tows a captured Polish 37 mm Armata przeciw-panzerna wz.36 anti-tank gun.

Tolik Shpigel

The next day, the Germans switched tactics and begun plastering the Rzegnów position on the right flank of the Polish forces with heavy artillery fire for two straight hours.

With the bombardment then ending, Petzel’s troops attacked again and this time started cracks started to appear in the battered Polish defences, unsurprising given the ferocity and determination of the German efforts.

Polish soldier in the trench at Mława.

One of the bunkers with damage visible on the exterior.

To relieve the pressure, the Poles counterattacked with the 79th Infantry Division but when this failed to make any progress, the General Krukowicz-Przedrzymirski ordered the 20th Division toextend it’s position further eastwards to cover its right flank between the villages of Dębsk and Nosarzewo and to provide a link with the Mazovian Cavalry Brigade, who were further eastwards and facing German armoured troops. The Polish 8th Infantry Division – held in reserve up until that point – were then ordered to counterattack.

Polish 37mm anti-tank gun and crew during the Invasion of Poland. The German Panzer I and II's proved vulnerable to such weaponry throughout the Invasion.


In the early morning of 3rd September, the 8th Division set off, splitting into two separate forces: Once advancing towards Grudusk east of Mława and the other towards Przasnysz.

However, poor communications and the actions of German saboteurs operating behind Polish lines hampered both attacks and caused confusion and disarray.

As a result, the Division was decimated by the Germans with only the 21st Infantry Regiment – led by Colonel (later General) Stanisław Sosabowski - managed to withdraw in any sort of order and fell back to the Modlin Fortress.

However, the Germans were still unable to breach the 20th Divisions defences.

German soldiers during the battle of Mława

German breakthrough

Later that day though, German engineers managed to finally break through the Polish anti-tank barriers and by using local civilians as a human shield – a reprehensible yet effective tactic – they were finally able to capture several of the Polish bunkers on the left flank - although were unable to advance any further.

On the Polish right flank close to the swamp area, the German “Wodrig” Corps finally cut through the Polish 79th Infantry Regiments defences and started to strengthen their position.

Waffen-SS soldiers during the Battle of Mława.

Panzer III advancing of Mława.

“The infantry (SS Reg.Deutschland) of the division (Panzerverband Kempf) on our left crossed the border south of Neidenburg 1 September 1939, in order to advance on the polish position located a few miles to the south near Mlawa (sketch Nº 1).

These positions consisted of concrete machine gun nest connected by trenches and protected in front by barbed wire and tank barriers (sketch Nº 2). The germans had no information concerning the size of the area covered by this defensive system and the nature of its construction.

Sketch No. 1: Highlighting the Polish positions.

About 6 AM the infantry (SS Reg.Deutschland) occupied Bialuty without encountering much resistence and from there it continued its advance toward the south. At 06:40 AM the reconnaissance detachment (SS A.A.) was ordered to move to Bialuty by motor and to reconnoiter the country west of that locality, where in the area west of the Bialuty woods, a German infantry division was attacking southward (ID 61). At 07:05 AM we crossed the polish border at a point southeast of Krokau and shortly thereafter arrived at Bialuty where we established our command post in the church. Near the southwestern exit of Bialuty we came upon a road block consisting in trees and concealed mines, an obstacle which presented but little difficulty, as we were able to pass around it quite easily despite our heavy transportation.

Sketch No. 2: Highlighting the Polish trenches and barbed wire.

At 08:00 AM three patrols were sent out from the reconnaissance detachment (SS A.A.) with order as follows:


  • Patrol Nº 1 to reconnoiter the Bialuty - Brodowo highway as far as the western edge of the wood.
  • Patrol Nº 2 to reconnoiter the road leading through the wood toward the southwest as far as the western edge of the wood.
  • Patrol Nº 3 to proceed to Ilowo and, while en route, to post a picket at the souhtwestern edge of the wood.


Up to 08:40 AM reports had been coming in that the wood was clear of enemy, whereupon the reconnaissance detachment (SS A.A.) proceeded to the southeast corner of the wood and halted. Here it concealed its vehicles in the wood camouflaging them against observation from the air and established a local outpost to the south.

In the meantime patrol nº 3 contacted some Poles that were still facing northward: they occupied a position east of Janowo. They were fired on by our scout cars, an action which facilitated the advance of neighbouring friendly troops moving down from the north. This patrol also reported that there were no Poles in Sochy and that the adjoining division (ID 61) had reached Ilowo. The entire patrol then returned to the detachment.

Friendly artillery had been concentrating on the polish position since 10:00 AM . The polish artillery responded and some of their fire covered the corner of the wood where the reconnaissance detachment (SS A.A.) was located. With exception of one minor casualty, losses were avoided by hastily entrenching in front of the wood; the transportation as well as the artillery south and west of Bialuty suffered negligible damage and but few casualties.

In the interim the infantry (SS Reg. Deutschland) had pushed forward as far as the line of block-houses. The Corps (I AK) had attached the tank regiment of our division (Pz Reg 7) to the division on our left (ID 11). This regiment attacked in the area south of Kuklin as far as the tank barriers.

Felix Steiner, commander of the Deutschland Regiment, observes the enemy during the invasion of Poland. The regiment was part of Army Group North’s thrust into Poland from East Prussia.

The division (Panzerverband Kempf) received orders to attack in the afternoon following the artillery preparation. The reconnaissance detachment (SS A.A.) having been ordered to provide security for covering the gap between our division and the one on the right (ID 61), sent out a combat group with instructions to proceed in the direction of Pikielko. Upon reaching Szcepka this group suddenly came under heavy hostile fire, which it returned with some degree of success. However its progress was interrupted when it reached the line of block-houses. The infantry likewise was able to make but little progress during the course of the afternoon. The combat group was withdrawn to some extend during the night which with the exception of friendly harassing artillery fire passed rather quietly. Some Poles taking advantage of the darkness deserted to the German lines.”


With the line now broken, the Poles began to withdraw on the 4th September, harassed and bombed by the Luftwaffe as they retreated south of Mława, with the lightly forested area providing little cover which resulted in significant losses in both men and equipment. Fortunately for the Poles, the German armoured units were themselves too battered to mount any meaningful pursuit. In fact, the German losses were damaging enough to hamper progress in this area – even after the main Polish forces had withdrawn – it wasn’t until the 13th September that they finally reached the area of the forbidding Modlin Fortress, where the surviving elements of the Polish 8th and 20th divisions had themselves withdrawn to.   

With the eventual occupation of Poland, Mława itself was eventually annexed to Nazi Germany on 26 October 1939 and came under the control of Regierungsbezirk Zichenau (administrative region, of the Nazi German Province of East Prussia.) The Germans established and operated two forced labour camps in the town.

Mława after the battle.

Polish prisoners after the battle.