Germany invaded Poland at 4:45 on the morning of September 1, 1939, on the bet that Britain and France would back down as they had over Czechoslovakia the year before — this time, they did not

Adolf Hitler had watched Britain and France accept the dismemberment of Czechoslovakia without firing a shot. What he had not planned for was Poland being the year they stopped.

What happened at Gleiwitz?

The night before the invasion, SS officers in Polish army uniforms staged a fake raid on the German radio station at Gleiwitz, near the Polish border in Upper Silesia. Alfred Naujocks led the team; Reinhard Heydrich, head of the Reich Security Main Office, had ordered it. They fired a few shots and broadcast a brief anti-German message in Polish, then left behind a body. Franciszek Honiok was a Silesian farmer with Polish sympathies who had been arrested days earlier, drugged, and shot to look like a saboteur killed in the act. The Gestapo's own paperwork referred to bodies prepared this way as "Konserve" (canned goods).

It was one of a handful of staged border incidents that week, and none of them fooled anyone outside Germany. Foreign correspondents who reached Gleiwitz the next day found no evidence of a Polish attack, because there had not been one.

The first shots, at Westerplatte

The real invasion had begun minutes earlier, along the coast at Danzig. The German pre-dreadnought battleship Schleswig-Holstein had moored in the harbor a week before, ostensibly on a goodwill visit; roughly two hundred marines were hidden below decks. At 4:45 a.m. she opened fire, at point-blank range, on the Westerplatte peninsula, a Polish military transit depot held by about two hundred men under Major Henryk Sucharski.

Danzig's own residents got the news that same morning. In the city center, Free City police and SS auxiliaries attacked the Polish Post Office, defended for fifteen hours by fifty-seven postal workers and militiamen before it fell. The postmaster, Józef Wąsik, was burned alive by a flamethrower as he tried to surrender. Survivors were tried by a German court-martial and shot by firing squad in early October, under a wartime law that had not existed when they gave up.

Westerplatte's garrison, badly outnumbered, held for seven days against a force fifteen times its size. It became postwar Poland's most durable image of the invasion, not because the depot mattered strategically (it did not) but because of how long two hundred men managed to hold ground against thousands.

What Hitler told the Reichstag

At eleven that morning, Hitler addressed the Reichstag at the Kroll Opera House, wearing a field-grey military tunic instead of his usual party brown, and announced that Germany had been under attack since before dawn. "Since 5:45 this morning, we have been returning fire," he said, framing the invasion as a defensive response to Polish provocations: the ones his own intelligence service had spent the night manufacturing.

The claim did not even match his own timeline. The Schleswig-Holstein had opened fire a full hour earlier, at 4:45. Whether the mismatch was a drafting error or simple carelessness about a lie nobody expected to be checked has never been established. It went unremarked in the chamber regardless.

Was Wieluń a legitimate target?

Also that morning, Luftwaffe bombers hit Wieluń, a market town with no garrison and no anti-aircraft guns. Waves of Junkers dropped roughly 380 bombs over nine hours, destroying about seventy percent of the town's buildings, among them the hospital and two churches.

Early Polish estimates put the dead above two thousand. Later research complicates that badly. A 2004 study by Poland's Institute of National Remembrance and later work by the historian Tomasz Piątkowski both found a confirmed toll in the low hundreds; the higher figures appear to have counted deaths across the surrounding county rather than the town itself. What is not in dispute is that Wieluń had no military value, and that its own hospital, Red Cross markings presumably visible from the air, was among the first buildings hit.

Why did Britain and France take two days?

Britain's formal alliance with Poland was six days old: a treaty signed on August 25, rushed through once the Molotov-Ribbentrop Pact removed the one thing that might have stopped Hitler. France's commitment went back to 1921 and had a longer history of finding reasons to wait. Both governments spent September 1 and 2 chasing a face-saving Italian mediation proposal that Benito Mussolini floated and Hitler ignored, buying time nobody in Warsaw wanted spent.

By the evening of September 2, the delay had become its own scandal. Members of the House of Commons openly asked whether their government intended to honor the guarantee at all. Neville Chamberlain's ambassador delivered a final note in Berlin on the morning of the 3rd, demanding a German withdrawal by 11:00. None came. At 11:15, Chamberlain told the country by radio: "I have to tell you now that no such undertaking has been received, and that consequently this country is at war with Germany." France declared war that same evening.

What the gamble cost

Poland fought on alone for weeks, expecting the western offensive that never came. French and British forces stayed largely on the defensive through what became known, with some bitterness, as the Phony War. On September 17, the Soviet Union invaded from the east under the secret protocol of the Molotov-Ribbentrop Pact, and by early October Poland had been divided between two occupying powers.

Hitler's bet on Western passivity had been reasonable, given the year before it. Munich had taught him that a democracy under domestic pressure will trade someone else's border for a headline about peace, and he built his September timetable on that lesson. It was the one calculation of 1939 he got wrong, and it turned a regional war he expected to fight and win in isolation into a European one he did not.

Poland itself paid first and longest: six years of occupation and roughly six million dead, with a postwar border redrawn hundreds of miles to the west. The radio station at Gleiwitz still stands, in what is now the Polish city of Gliwice, with a small museum inside: a monument, more or less by accident, to the one lie of the war that nobody outside Germany ever believed and that started it anyway.

Sources

• Wikipedia, "Invasion of Poland"
• Wikipedia, "Gleiwitz incident"
• Wikipedia, "Battle of Westerplatte"
• Wikipedia, "Bombing of Wieluń"
• Wikipedia, "1 September 1939 Reichstag speech"
• Wikipedia, "Polish Post Office in Danzig"