📅 On This Day in Military History

September 20

5 events across history

⚔️📍 Salamis Strait, Greece480 BC

Battle of Salamis — Greek Navy Destroys Persia's Fleet

Athenian Admiral Themistocles lured the massive Persian fleet into the narrow Salamis strait, where numbers were irrelevant and Greek triremes' superior maneuverability proved decisive. Around 200 Persian ships were sunk or captured.

Salamis saved Greek civilization from Persian conquest and set the stage for the final Persian defeat at Plataea; the battle is considered one of the most consequential in history.

Outcome

Greek victory; Persian invasion repelled

Casualties

40,000

The Norman Conquest of England1066

Battle of Fulford

The Norwegian king Harald Hardrada, allied with Harold Godwinson's exiled brother Tostig, landed a great fleet on the Yorkshire coast and advanced on York. The northern earls Edwin and Morcar met them at Fulford, just south of the city. After hard fighting the Viking line held and then crushed the English flank against the river, scattering the northern levies and opening York to the invaders.

Fulford broke the military power of northern England and forced King Harold to march his army the length of the country at desperate speed. It set up the lightning campaign that would exhaust the English even before William's Normans landed in the south — a fateful drain on Harold's strength.

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⚔️English Civil War1643

First Battle of Newbury

The Royalist army attempted to intercept the Earl of Essex's force returning to London after relieving Gloucester. Fighting around the town and surrounding fields was intense and see-saw throughout the day. Parliamentary infantry and musketeers held their ground against Royalist cavalry charges. By nightfall the Royalists had run low on ammunition and withdrew, leaving the road to London open.

First Newbury was Parliament's first major defensive success. Essex had relieved Gloucester under the King's nose and then fought his way back to London — a major propaganda and strategic victory. The battle also marked the death of the young Lord Falkland, Secretary of State and one of the most admired moderate figures of the age, who rode deliberately into the fighting — apparently seeking death at the prospect of his country's ruin.

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🔴The French Revolutionary Wars1792

Battle of Valmy

Valmy was not a great battle by any conventional measure — casualties were minimal, the fighting lasted only hours, and the opposing armies barely closed. But it was one of the most consequential military engagements in history. The Duke of Brunswick's Prussian army — the finest professional force in Europe — advanced on the French position at Valmy and was met by a sustained artillery duel followed by something unprecedented: French citizen soldiers, raw recruits of the revolutionary army, chanting 'Vive la Nation!' and refusing to break. Brunswick, who had expected professional French soldiers to collapse under pressure and had never imagined they might hold on ideology alone, paused, reconsidered, and ordered a retreat. The road to Paris was open — and he chose not to take it.

Valmy saved the French Revolution. Had Brunswick's Prussians broken through to Paris — and there was every military reason to believe they would — the monarchy would have been restored and the Revolution suppressed. Instead, the citizen army's stand confirmed that something new had entered warfare: troops who fought for an idea rather than a wage, and who would die rather than retreat. Goethe, present with the Prussian army, wrote that night: 'From this place and this time forth commences a new era in the world's history.'

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The Crimean War1854

Battle of the Alma

The first major land battle of the Crimean War was fought at the Alma River, where Menshikov had positioned Russian forces on heights commanding the road to Sevastopol. Allied forces — British on the right, French on the left — crossed the river under fire and stormed the Russian positions. French forces scaled the cliffs on the left flank while British infantry advanced through withering musket fire. Russian resistance collapsed after roughly three hours.

The Alma demonstrated Russian tactical weakness against the Allied combination of rifled weapons (which had longer range and greater accuracy than Russian smoothbore muskets) and aggressive infantry tactics. Menshikov's failure to construct field fortifications or properly deploy his artillery wasted every natural advantage the heights provided. The Allied victory opened the road to Sevastopol, though the failure to pursue aggressively allowed the Russian field army to escape intact.

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