duchy. On 10 June 1609, they signed the , rejecting all other claimants and establishing a provisional government together with the local estates. Their troops entered the duchy in defiance to the acting regency and the Emperor. In January 1610, Henry IV of France signed a draft military pact with the Protestant Union and dispatched 22,000 men under Marshal de La Chatre to north–eastern France. A comparable number of troops was dispatched by the Dutch towards Schenkenschanz in an apparent show of force towards Spain. Archduke Leopold V sought to raise his profile in the ongoing power struggle between the Emperor and Archduke Matthias by convincing the former to annul the Treaty of Dortmund and appoint him as the imperial to commissioner. Leopold triumphantly entered Jülich, but he soon found himself besieged by an army three times his size, as fighting spread to Aachen and Düren. The struggle between the Catholic royal family and the Protestant princes brought fears of a larger religious war. The Protestant Union mobilized 5,000 men, and Leopold recruited 1,000 cavalry and 3,000 infantry in the Prince-Bishopric of Strasbourg. His Habsburg relatives and the rest of the Catholic League refused to support Leopold openly and gathered troops only for their own protection. On 13 March 1610, Protestant Count Otto von Solms–Braunfels invaded Strasbourg with 2,000 troops. The Catholics simply retreated into walled towns such as Saverne and waitef until the ill–disciplined invaders ran out of money and retreated. A meeting was set in Prague on 1 May 1610 to broker a settlement. Rudolf's initial decision to enfeoff the entire duchy to Christian II, Elector of Saxony, was rejected by a number of moderate princes, which led to the postponement of negotiations until August. A second Protestant invasion, this time consisting of 9,800 troops and artillery, succeeded in seizing Dachstein, Mutzig and Molsheim, but it too was brought to halt after the local population had refused to supply it food. In the meantime, Leopold had fled Jülich and left 1,500 troops inside. Their fate was sealed as the Kingdom of France and the Dutch Republic finally intervened in support of the Protestants and aimed to antagonise Spain by putting further pressure on the Spanish Road. The Dutch intercepted a relief party heading from the Prince-Bishopric of Liège and bolstered the besiegers into a combined total of 25,200 troops. On 1 September, the garrison surrendered in return for