Modlin — Thommée at the last fortress

Built by Napoleon I in 1806-1812, modernised by the Russians in the nineteenth century and again by the Poles in the 1920s and 1930s, the Modlin fortress guards the junction of the Vistula and the Narew, 30 km north-west of Warsaw. On 1 September, its standing garrison numbers only about 5,000 men; but from 9 September onward the remnants of General Krukowicz-Przedrzymirski's Modlin Army and fragments of the Pomorze and Poznań Armies fall back into it.

Wiktor Thommée, 58, takes command on 13 September by decree of Rydz-Śmigły. By the 15th the fortress shelters nearly 35,000 men, including 4,000 wounded; to support them, Thommée musters 134 guns — Schneider, Bofors, vz.30 — twelve light tanks and the garrisons of the two works at Modlin and Zakroczym.

German attacks begin on 13 September. Bock's Heeresgruppe Nord entrusts Modlin's capture to Küchler's 3rd Army, four infantry divisions strong and supported by Kesselring's Luftflotte 1: Stukas, 150 and 210 mm heavy artillery, Karl mortars hammer the works. Modlin holds out. On 18 September, two German armoured divisions — Reinhardt's and Kempf's — are withdrawn southward; the Polish garrison is still standing.

But by 27 September Warsaw has surrendered. Modlin has no shells left for its heavy artillery, no drinking water since the pumps were destroyed, not a single bandage left for its 4,000 wounded. Typhus breaks out. Thommée must decide.