 Shortly after two of Ferdinand's generals, Ottavio Piccolomini and Prince Thomas of Carignano, routed in command of an Imperial-Spanish force the French army under the Marshals Gaspard III de Coligny and Jacques-Nompar de Caumont, which retreated from Saint Omer with the loss of 4,000 men.Piccolomini's Imperials also overran some Dutch outposts in Cleves.In an attempt to restore the situation, Frederick Henry laid siege to Geldern in command of 16,000 men, but was forced into a costly retreat by the Cardinal-Infante, who succeeded in breaking his lines of circumvallation.