English Civil War with his army from Scotland. On 4 April 1660, in the Declaration of Breda, Charles II made known the conditions of his acceptance of the Crown of England. Monck organised the Convention Parliament, which met for the first time on 25 April 1660. On 8 May 1660, it declared that King Charles II had reigned as the lawful monarch since the execution of Charles I in January 1649. Charles returned from exile on 23 May 1660. On 29 May 1660, the populace in London acclaimed him as king. His coronation took place at Westminster Abbey on 23 April 1661. These
Treaty of Copenhagen (1660) had already agreed with England that preventing the western and eastern shore of Øresund from being controlled by the same country would in turn prevent future raises of the Øresund toll, which would cause disruption in the Dutch and English Baltic trade. In addition, Cardinal Mazarin threatened a French invasion of the Netherlands if it were to assist Denmark against Sweden. When learning of Charles' death in February 1660, Frederick immediately proclaimed the Treaty of Roskilde null and void. This caused great alarm to the Swedish mediators, but their French and English counterparts assured them that if Sweden were to