On 12 October, Luigi Mattei led 12,000 infantry and up to 4,000 cavalry against the fortified town. The pope's forces were met by a contingent of 40 troops guarding a bridge leading to the town; a short burst of cannon-fire resulting in a single death was enough to prompt capitulation. Castro, and several other small towns nearby, surrendered. Fabrizio Savelli, though, proved to be an unenthusiastic commander. The army was split into three and the Pope's nephew, Taddeo Barberini, replaced Savelli as Generalissimo, arriving with one contingent in the papal city of Ferrara on 5 January 1642. On 11 January the opera "L'Armida", by Barberini house composer Marco Marazzoli, was presented in his honour and Marazzoli composed a work "Le pretensioni del Tebro e del Po" to commemorate recent events.