The Étaples Mutiny was an uprising that began on this day in 1917, committed by British Army and Imperial soldiers in the Northern French coastal port of Étaples during World War I.

The soldiers were enrolled in a training camp there. On the other side of the river was the beach resort known officially as "Le Touquet-Paris-Plage". Le Touquet was, in effect, officers' territory, and pickets were stationed on the bridge over the Canche to enforce this.

On September 9th, 1917, Gunner A. J. Healy, who had been walking along the river at low tide, attempted to return across the bridge. He was apprehended by the guards and accused of being a deserter.

Upon hearing this, soldiers from the camp formed an angry mob and moved towards the town, failing to disperse even after being told that Healy had been released. His arrest had become the catalyst for open rebellion after years of soldiers' discontent.

The soldiers clashed with police, who shot openly into the crowd, killing one soldier and wounding a French bystander. Open mutiny continued for days before being put down by force and mass arrests on September 12th.

Corporal Jesse Short was convicted of attempted mutiny and executed by firing squad. Many other soldiers received lesser punishments, ranging from demotion in rank and fines to as many as ten years in prison.

According to freelance author David Lamb, the Étaples Mutiny was part of a rising tide of British mutinies which continued throughout 1918, reaching a peak in the winter of 1918 - 1919. Military police fired on strikers and mutineers, killing at least 27 in the month of September 1917 alone.