The last great event of the War of the Spanish Succession was the Duke of Berwick's storming of Barcelona, after a long siege, on 11 September 1714. In that year, he was appointed a Knight of the Golden Fleece. Trying to explain the failure of the Jacobite Risings, the Old Pretender "never forgave his half-brother, The Blues ex-colonel, Berwick, now an experienced and competent commander, for declining to lead his forces". Soon afterwards, Berwick was appointed military governor of the province of Guienne, where he became friendly with Montesquieu. In December 1718 he led an army to Spain, against Philip V, in the War of the Quadruple Alliance, bombarding San Sebastián and occupying the districts of Gipuzkoa and Biscay. Many years of peace followed this campaign that ended the following March. The King of Spain sued for peace in January 1720 and Berwick was not called to serve again in the field until 1733. In that year he was chosen to lead the Army of the Rhine in the War of the Polish Succession, successfully besieging Kehl in 1733. A year later he was decapitated by a cannonball at the Siege of Philippsburg, on 12 June 1734.