Napoleon Bonaparte had jailed Pius VI who died in jail. When Pope Pius VII was elected he too was jailed by Bonaparte, who kept him prisoner at Fontainbleau. The Holy Father vowed to God that if he were restored to the Roman See, he would institute a special feast in honour of Mary. The military eventually forced Bonaparte to release the Pope and on 24 May 1814, Pius VII returned in triumph to Rome. Twelve months later the Pope decreed that the feast of Mary Help of Christians be kept on 24 May.