Spain and the Pope.=] Maximilian of Bavaria took the lead. Stipulating as his reward the electoral hat which was to be torn from the head of Frederick, and the right of occupying upper Austria as security for his expenses, he placed his army and the resources of the League at Ferdinand’s disposal. In March 1620, under his auspices, a meeting of the League was arranged with the elector of Saxony at Mülhausen, and an agreement arrived at by which the League undertook not to attempt to recover the lands of the Protestant bishops and administrators in north Germany, as long as they continued loyal to the Emperor. This arrangement, though no solution of the question of the ecclesiastical lands, secured at any rate for the time the neutrality of Saxony and the Lutheran princes. The Pope sent money to swell the resources of the League, and Philip of Spain agreed to march troops from the Netherlands to attack the Palatinate. [Sidenote: =The war national and religious.=] The campaign of 1620 opened, therefore, under very different circumstances from those of 1619. The war had already become a German war. With the certainty of the intervention of Spain and the Pope, with the possibility of that of England, it threatened to assume an European character. With the League on the one side and the Union on the other, it was a war of creeds. [Sidenote: =Importance of Bavaria. Policy of Maximilian.=] From a military as well as a political point of view, the accession of Maximilian of Bavaria to the cause of the Emperor made all the difference. Weak in health, and unpleasing in appearance, he concealed under an insignificant exterior an iron will and a faultless judgment. He alone among his contemporaries in Germany had the statesman’s faculty of knowing exactly what was possible. He never struck except to succeed. He never ventured without being sure of his ground. Succeeding to an impoverished exchequer, and a territory disjointed in extent and divided in religion, he had set before himself as the objects of his policy, the supremacy of Catholicism, the consolidation of his dominions, and the acquisition of the electoral dignity. By thrift and good management he had amassed considerable treasure, and had carefully trained a powerful army, which he had intrusted to the command of the Walloon Tilly, who had the reputation of being the greatest general of the day. His opportunity was now come, and he threw himself zealously into the war of ambition and religion with the proud consciousness that he was the real leader of the Catholic cause and the saviour of the House of Austria. In June the toils began to close round the ill-fated Frederick. Philip III., convinced through Gondomar’s diplomacy that James I. would not break his neutrality even though the Palatinate was invaded, sent the necessary orders to Spinola, and by August the Spanish army was at Mainz. At the end of June, Tilly crossed the frontier into Austria,