Frederick accepted the Bohemian crown. The coronation was celebrated with unexampled pomp at Prague, for the nation displayed all its riches in honour of its own work. Silesia and Moravia, the adjoining provinces to Bohemia, followed their example, and did homage to Frederick. The reformed faith was enthroned in all the churches of the kingdom; the rejoicings were unbounded, their attachment to their new king bordered on adoration. Denmark and Sweden, Holland and Venice, and several of the Dutch states, acknowledged him as lawful sovereign, and Frederick now prepared to maintain his new acquisition.
His principal hopes rested on Prince Bethlen Gabor of Transylvania. This formidable enemy of Austria, and of the Roman Catholic church, not content with the principality which, with the assistance of the Turks, he had wrested from his legitimate prince, Gabriel Bathori, gladly seized this opportunity of aggrandizing himself at the expense of Austria, which had hesitated to acknowledge him as sovereign of Transylvania. An attack upon Hungary and Austria was concerted with the Bohemian rebels, and both armies were to unite before the capital. Meantime, Bethlen Gabor, under the mask of friendship, disguised the true object of his warlike preparations, artfully promising the Emperor to lure the Bohemians into the toils, by a pretended offer of assistance, and to deliver up to him alive the leaders of the insurrection. All at once, however, he appeared in a hostile attitude in Upper Hungary. Before him went terror, and devastation behind; all opposition yielded, and at Presburg he received the Hungarian crown. The Emperor's brother, who governed in Vienna, trembled for the capital. He hastily summoned General Bucquoi to his assistance, and the retreat of the Imperialists drew the Bohemians, a second time, before the walls of Vienna. Reinforced by twelve thousand Transylvanians, and soon after joined by the victorious army of Bethlen Gabor, they again menaced the capital with assault; all the country round Vienna was laid waste, the navigation of the Danube closed, all supplies cut off, and the horrors of famine were threatened. Ferdinand, hastily recalled to his capital by this urgent danger, saw himself a second time on the brink of ruin. But want of provisions, and the inclement weather, finally compelled the Bohemians to go into quarters, a defeat in Hungary recalled Bethlen Gabor, and thus once more had fortune rescued the Emperor.
In a few weeks the scene was changed, and by his prudence and activity Ferdinand improved his position as rapidly as Frederick, by indolence and impolicy, ruined his. The Estates of Lower Austria were regained to their allegiance by a confirmation of their privileges; and the few who still held out were declared guilty of `lese-majeste' and high treason. During the election of Frankfort, he had contrived, by personal representations, to win over to his cause the ecclesiastical electors, and also Maximilian, Duke of Bavaria, at Munich. The whole issue of the war, the fate of Frederick and the Emperor, were now dependent on the part which the Union and the League should take in the troubles of Bohemia. It was evidently of importance to all the Protestants of Germany that the King of Bohemia should be supported, while it was equally the interest of the Roman Catholics to prevent the ruin of the Emperor. If the Protestants succeeded in Bohemia, all the Roman Catholic princes in Germany might tremble for their possessions; if they failed, the Emperor would give laws to Protestant Germany. Thus Ferdinand put the League, Frederick the Union, in motion. The ties of relationship and a personal attachment to the Emperor, his brother-in-law, with whom he had been educated at Ingolstadt, zeal for the Roman Catholic religion, which seemed to be in the most imminent peril, and the suggestions of the Jesuits, combined with the suspicious movements of the Union, moved the Duke of Bavaria, and all the princes of the League, to make the cause of Ferdinand their own.
According to the terms of a treaty with the Emperor, which assured to the Duke of Bavaria compensation for all the expenses of the war, or the losses he might sustain, Maximilian took, with full powers, the command of the troops of the League, which were ordered to march to the assistance of the Emperor against the Bohemian rebels. The leaders of the Union, instead of delaying by every means this dangerous coalition of the League with the Emperor, did every thing in their power to accelerate it. Could they, they thought, but once drive the Roman Catholic League to take an open part in the Bohemian war, they might reckon on similar measures from all the members and allies of the Union. Without some open step taken by the Roman Catholics against the Union, no effectual confederacy of the Protestant powers was to be looked for. They seized, therefore, the present emergency of the troubles in Bohemia to demand from the Roman Catholics the abolition of their past grievances, and full security for the future exercise of their religion. They addressed this demand, which was moreover couched in threatening language, to the Duke of Bavaria, as the head of the Roman Catholics, and they insisted on an immediate and categorical answer. Maximilian might decide for or against them, still their point was gained; his concession, if he yielded, would deprive the Roman Catholic party of its most powerful protector; his refusal would arm the whole Protestant party, and render inevitable a war in which they hoped to be the conquerors. Maximilian, firmly attached to the opposite party from so many other considerations, took the demands of the Union as a formal declaration of hostilities, and quickened his preparations. While Bavaria and the League were thus arming in the Emperor's cause, negotiations for a subsidy were opened with the Spanish court. All the difficulties with which the indolent policy of that ministry met this demand were happily surmounted by the imperial ambassador at Madrid, Count Khevenhuller. In addition to a subsidy of a million of florins, which from time to time were doled out by this court, an attack upon the Lower Palatinate, from the side of the Spanish Netherlands, was at the same time agreed upon.
During these attempts to draw all the Roman Catholic powers into the League, every exertion was made against the counter-league of the Protestants. To this end, it was important to alarm the Elector of Saxony and the other Evangelical powers, and accordingly the Union were diligent in propagating a rumour that the preparations of the League had for their object to deprive them of the ecclesiastical foundations they had secularized. A written assurance to the contrary calmed the fears of the Duke of Saxony, whom moreover private jealousy of the Palatine, and the insinuations of his chaplain, who was in the pay of Austria, and mortification at having been passed over by the Bohemians in the election to the throne, strongly inclined to the side of Austria. The fanaticism of the Lutherans could never forgive the reformed party for having drawn, as they expressed it, so many fair provinces into the gulf of Calvinism, and rejecting the Roman Antichrist only to make way for an Helvetian one.
While Ferdinand used every effort to improve the unfavourable situation of his affairs, Frederick was daily injuring his good cause. By his close and questionable connexion with the Prince of Transylvania, the open ally of the Porte, he gave offence to weak minds; and a general rumour accused him of furthering his own ambition at the expense of Christendom, and arming the Turks against Germany. His inconsiderate zeal for the Calvinistic scheme irritated the Lutherans of Bohemia, his attacks on image-worship incensed the Papists of this kingdom against him. New and oppressive imposts alienated the affections of all his subjects. The disappointed hopes of the Bohemian nobles cooled their zeal; the absence of foreign succours abated their confidence. Instead of devoting himself with untiring energies to the affairs of his kingdom, Frederick wasted his time in amusements; instead of filling his treasury by a wise economy, he squandered his revenues by a needless theatrical pomp, and a misplaced munificence. With a light-minded carelessness, he did but gaze at himself in his new dignity, and in the ill-timed desire to enjoy his crown, he forgot the more pressing duty of securing it on his head.