 After three months of combat in the Siege of Saint-Martin-de-Ré against the French under Marshal Toiras, the Duke was forced to withdraw.The English lost more than 4,000 out of 7,000 troops during the campaign.The main port, Saint-Martin, was fortified by Vauban in 1681 as a component of the belt of forts and citadels built to protect the military harbour of Rochefort.