as Obristwachtmeister and commander of an infantry regiment. He was second officer to Count Anholt and distinguished himself, especially at the battle of Stadtlohn (1623). After being promoted to colonel in 1625 and made Reichsfreiherr in 1627, the League president and Bavarian Elector Maximilian denied him further promotion, leading to Gallas' change into Imperial service in early 1629. Since 1629, he was serving as Generalfeldwachtmeister under Count Collalto in the War of Mantuan succession. When Collalto fell sick, command of the Imperial army devolved to his deputies, Gallas and Johann von Aldringen. On 29 May 1630, Gallas successfully defeated a 17,000 strong Franco-Venetian relief army led by the French general Duc de Candale and the Venetian provveditore Zaccaria Sagredo at the battle of Villabuona. His complete victory at Villabuona ensured the fall of Mantua, and on 18 July Imperial troops under his command captured and then brutally sacked the city. Only the churches and the ghetto were spared, but the latter solely to expel the Jewish population and to plunder it nine days later. The expulsion was later rescinded by the Imperial court, and on 18 October the surviving Jewish population of Mantua was allowed to return. Gallas stayed in Italy to negotiate the Treaty of Cherasco in which he managed to prevent the demilitarisation of the Valtellina that remained under Imperial control. Made Imperial Count for the capture of Mantua and the negotiations at Cherasco, he returned to Germany for the campaign against the invading swedish king Gustavus Adolphus and his Saxon allies in late 1631. Gallas was appointed to Feldzeugmeister and assumed command over a corps of Wallenstein's army. Over the winter, he recovered parts of Bohemia from Saxon occupation. Wallenstein's army recaptured Prague and subsequently turned to Bavaria to face the Swedish army in 1632. Gallas' corps served at the Battle of the Alte Veste near Nuremberg against the Swedish King. After the battle, Gallas was promoted to Field Marshal. Wallenstein sent him to Silesia prior to the Battle of Lützen and called him back too late, so that he did not arrive in time to participate. On a proposal from Wallenstein, Emperor Ferdinand II appointed Gallas to Generalleutnant, second-in-command to the Generalissimo. Over the year 1633, he commanded in Silesia. When Wallenstein's repeated disobedience and unauthorized negotiations with Saxony strengthened the court's mistrust of him, the Imperial counselor Wolkenstein contacted Gallas to check his loyalty and