Even now, it was merely the disunion of its members, and the intolerance of religious zeal, that paved the way for the Swedish invader.  The bond of union between the states, which alone had rendered the Empire invincible, was now dissolved; and Gustavus derived from Germany itself the power by which he subdued it.  With as much courage as prudence, he availed himself of all that the favorable moment afforded; and equally at home in the cabinet and the field, he tore asunder the web of the artful policy, with as much ease, as he shattered walls with the thunder of his cannon.  Uninterruptedly he pursued his conquests from one end of Germany to the other, without breaking the line of posts which commanded a secure retreat at any moment; and whether on the banks of the Rhine, or at the mouth of the Lech, alike maintaining his communication with his hereditary dominions.

[Illustration:  GUSTAVUS ADOLPHUS]

The consternation of the Emperor and the League at Tilly’s defeat at Leipzig, was scarcely greater than the surprise and embarrassment of the allies of the King of Sweden at his unexpected success.  It was beyond both their expectations and their wishes.  Annihilated in a moment was that formidable army which, while it checked his progress and set bounds to his ambition, rendered him in some measure dependent on themselves.  He now stood in the heart of Germany, alone, without a rival or without an adversary who was a match for him.  Nothing could stop his progress, or check his pretensions, if the intoxication of success should tempt him to abuse his victory.  If formerly they had dreaded the Emperor’s irresistible power, there was no less cause now to fear everything for the Empire from the violence of a foreign conqueror, and for the Catholic Church from the religious zeal of a Protestant king.  The distrust and jealousy of some of the combined powers, which a stronger fear of the Emperor had for a time repressed, now revived; and scarcely had Gustavus Adolphus merited, by his courage and success, their confidence, when they began covertly to circumvent all his plans.  Through a continual struggle with the arts of enemies, and the distrust of his own allies, must his victories henceforth be won; yet resolution, penetration, and prudence made their way through all impediments.  But while his success excited the jealousy of his more powerful allies, France and Saxony, it gave courage to the weaker, and emboldened them openly to declare their sentiments and join his party.  Those who could neither vie with Gustavus Adolphus in importance, nor suffer from his ambition, expected the more from the magnanimity of their powerful ally, who enriched them with the spoils of their enemies and protected them against the oppression of their stronger neighbors.  His strength covered their weakness, and, inconsiderable in themselves, they acquired weight and influence from their union with the Swedish hero.  This was the case with most of the free cities, and particularly