 However, William V and Maximilian of Bavaria ignored him when they and the three ecclesiastical electorsthe archbishops of Mainz, Trier and Cologneestablished the Catholic League in February 1610.Only Philip III of Spain, who promised financial aid to the League, could persuade the Catholic princes to accept Ferdinand as a director and the vice-protector of the League in August.Cooperating with Rudolph II's principal advisor, Melchior Klesl, Bishop of Vienna, Ferdinand persuaded the Emperor to seek a reconciliation with Matthias.