On ne passe pas

"They shall not pass" (French: Ils ne passeront pas!; Spanish: ¡No pasarán!) is a slogan used to express determination to defend a position against an enemy. "On ne passe pas" literally means "one does not pass"; this being a common French idiom to express interdiction.

It was most famously used during the Battle of Verdun in the First World War by French General Robert Nivelle. It appears on propaganda posters, such as that by Maurice Neumont after the Second Battle of the Marne, which was later adopted on uniform badges by units manning the Maginot Line. Later during the war, it also was used by Romanian soldiers during the Battle of Mărășești (the Romanian translation of the phrase is "Pe aici nu se trece").

It was also used during the Spanish Civil War, this time at the Siege of Madrid by Dolores Ibárruri Gómez, a member of the Communist Party of Spain, in her famous "No pasarán" speech on 18 July 1936. The leader of the nationalist forces, Generalísimo Francisco Franco, upon gaining Madrid, responded to this slogan by saying "Hemos pasado" ("We have passed").

"¡No pasarán!" was used by British anti-fascists during the October 1936 Battle of Cable Street, and is still used in this context in some political circles. It was often accompanied by the words nosotros pasaremos (we will pass) to indicate that communists rather than fascists will be the ones to seize state power.

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Wikipedia