On 31 May, Prince Rupert stormed Leicester; in response, Fairfax and the New Model Army abandoned their blockade of Oxford, and on 14 June, won a decisive victory at Naseby. Defeat cost the Royalists their most formidable field army, along with their artillery train, stores, and Charles' personal baggage. This included his private correspondence, detailing efforts to gain support from the Irish Catholic Confederation, the Papacy and France. Published by Parliament in a pamphlet entitled "The King's Cabinet Opened", it seriously damaged his reputation.