 In 1538, Charles II died without an heir, and the States of Guelders elected William, Duke of Jülich-Cleves-Berg to succeed him.William V eventually had to sue for peace in 1543, when all of Guelders, Zutphen and Jülich were occupied by Habsburg troops and France failed to come to his aid.The Treaty of Venlo forced him to relinquish Guelders and Zutphen to Charles V, and he had to commit himself to suppressing the rise of Protestantism in his remaining lands of Jülich, Cleves, Berg, Mark and Ravenstein, keeping his population Catholic.