During France's Wars of Religion in the 1620's, Cardinal Richelieu ordered the fortification of the Ile de Re, an island just off the coast of the city of La Rochelle, to counterbalance the Protestant Huguenots who ran that city. The Citadel of Saint-Martin was born.

In February of 1625, a gentleman by the name of Soubise led a Huguenot revolt against King Louis XIII, siezing the Ile de Re with 400 men. Fashioning himself "the Admiral of the Protestant Church," his fleet of 15 ships sailed up and down the coast, attacking the French navy and generally making a nuisance of himself.

In an amazing act of cooperation, the French, Dutch and English mounted an expedition to attack the Ile de Re in September 1625, proving that they cosidered Protestantism to be a greater threat to themselves than even each other. Soubise was driven off the island and fled to England.

Still a Protestant stronghold, La Rochelle was besieged by the forces of the King. In a turnaround that I don't even pretend to understand, the British invaded the Ile de Re in 1627 to relieve the siege, but after some three months of combat were forced to withdraw in defeat.

The port of Saint-Martin was improved by Vauban starting in 1681, which essentially surrounded the town with Vaubanesque pointy walls, integrating the Citadel into a huge fortress: This process was finished by 1702. This fortification was used for many years as a depot for French convicts on their way to penal settlements.

During the Second World War the Germans built several bunkers on the beaches of Ile de Re (though no one obliged them by attacking), and some scenes from the movie The Longest Day (1961) were shot there.

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