On the morning of September 1, 1939, in the small Polish village of Mokra, the air was thick with smoke and gunfire. Polish infantry fired from shattered, burning houses at the advancing German tanks. The German war machine, confident in its speed and firepower, roared forward — until a deep rumble emerged from the forest. Out of the trees came an armored train, its guns blazing. A German tank erupted into flames. For a moment, the unstoppable Blitzkrieg stumbled. The Nazis pulled back.
This was the opening chapter of Poland’s desperate fight — the battle that marked the beginning of World War II in Europe.
From World War I to a Precarious Independence
To understand 1939, we must go back to the end of World War I. Germany, defeated, was forced to surrender territory, shrink its army, and accept harsh peace terms. Among the liberated lands was Poland, reborn after over a century of foreign rule.
In the 1920s and 30s, Poland navigated a dangerous neighborhood. It signed a non-aggression pact with the Soviet Union, and forged alliances with France and the United Kingdom. The agreement was simple: if Poland were invaded, its allies would attack the aggressor. Poland, in turn, shared valuable military intelligence — including an early breakthrough in cracking Germany’s Enigma code — with both allies.
But even as Nazi Germany rose to power, Poland’s pleas for stronger military coordination were met with hesitation. When Polish generals urged Britain to allow full mobilization as German forces gathered on the border, London refused, fearing it might provoke Hitler. The Polish commander-in-chief instead ordered a “summer exercise” — a partial mobilization disguised to avoid diplomatic backlash.
Unequal Armor, Fierce Resistance
By 1939, Poland’s armored forces were small compared to Germany’s. Yet they had one remarkable machine: the 7TP light tank, fast, maneuverable, and capable of defeating early German Panzers.
At Piotrków Trybunalski, where the road to Warsaw lay wide open, Polish 7TPs lay hidden among trees and hills. When German tanks advanced, the Poles struck hard — shells hitting their mark, German armor bursting into flames. Fifteen enemy tanks were destroyed at the cost of seven Polish machines. The road to Warsaw was delayed, if only briefly.
Preparing for the Siege
By September 7, Warsaw’s defenders were ordered to hold the capital at all costs. The city would become a fortress — “a rock that would break Nazi teeth.” Civilians dug trenches, prepared oil traps for tanks, and braced for street-to-street fighting.
Polish filmmaker Julian Bryan documented the chaos: women shot while carrying potatoes, newborns huddled with mothers near burning buildings, artillery strikes turning neighborhoods into infernos. His footage would later earn international acclaim.
Meanwhile, France and Britain declared war on Germany — but their “Sitzkrieg” strategy meant only limited action on the Western Front. French forces advanced a few kilometers into Germany, then stopped. Poland waited in vain for a counterattack.
The Battle of Bzura and the Soviet Betrayal
In mid-September, Poland launched its largest counteroffensive of the campaign at the Bzura River. Initially, Polish forces pushed back the Germans, but the enemy quickly regrouped and surrounded them. A quarter of Poland’s army was trapped.
Then came a crushing blow. On September 17, Soviet forces invaded from the east. Many Poles initially thought the Red Army had come to help, but it was soon clear that the Molotov–Ribbentrop Pact — a secret agreement between Hitler and Stalin — had sealed Poland’s fate. The two powers would divide the country between them.
Last Stands and Flight to Freedom
As German and Soviet forces closed in, some Polish units made desperate escapes toward Romania and Hungary, destroying their own equipment to prevent capture.
One soldier, Roman Orlik, took position in a forest with a 20mm gun, destroying ten German vehicles in a single engagement, earning the rare title of a Polish tank ace. He would not escape, instead fighting in Warsaw’s final defense.
Warsaw Falls
By September 28, after three weeks of relentless bombardment, Warsaw’s defenders — exhausted, low on ammunition, and surrounded — were ordered to surrender. Over 40,000 soldiers and civilians had been killed in the capital’s defense. Fighting continued in isolated pockets for another week, but by October 6, organized resistance in Poland was over.
The cost had been immense for Germany and the Soviet Union, but Poland had fallen.
Aftermath and Legacy
Poland’s defeat was not the end of its war. Thousands of soldiers escaped to fight alongside the Allies, many serving in the French Army and later in the British forces — including at D-Day. At home, an underground resistance movement took root, sabotaging German operations for the next six years.
Though Poland had faced two of the most powerful militaries on Earth at once, it resisted for five weeks — longer than many thought possible. Its stand in 1939 became a symbol of defiance, sacrifice, and the unbroken will to fight for freedom.