But those were the victories of peace; he was at length forced to exhibit his qualities for war. In 1674, as a prince of the empire, he was compelled to furnish his contingent to its army against France. Louis XIV., in revenge, let loose the Swedes in Pomerania to invade Brandenburg. The reputation of the Swedish troops had risen to the highest rank in the Thirty Years' War, and they were regarded as all but invincible. The Prussian Elector, justly alarmed at this new peril of his dominions, appealed to his allies. But German alliances (in those days at least) were slippery, and German succours are habitually slow. Wearied by their delays, the Elector determined to act for himself. Breaking up from Franconia, he transferred his little army of eight thousand men suddenly to Magdeburg. The Swedes, encamped on the Havel, and contemptuous of Prussian strategy, took no trouble to ascertain his movements. The whole expedition was conducted with equal vigour and dexterity. On his arrival in Magdeburg, the gates were kept shut for four-and-twenty hours: thus all intelligence to the enemy was cut off. At nightfall he sallied forth; by daybreak he reached and assaulted the Swedish headquarters, took their baggage and cannon, and hunted the troops from post to post until their dispersion was total. This battle was one of the instances in which the most important results have followed from slight events. The battle would have been in later times scarcely more than an affair of advanced guards, for the Swedes had but eight thousand, and the Prussians engaged were but five thousand five hundred. But, to have beaten the most distinguished soldiery in Europe, to have surprised the most disciplined, and to have gained the victory with inferior numbers, instantly drew the eyes of Europe on the Elector. His dominions were subjected to no further insult; the character of the Prussian army was raised; and Prussia made the first actual stride to northern supremacy. This eminent man died in 1688, after a career which earned the panegyric even of his fastidious descendant, Frederick II., who thus described him, almost a hundred years after:-- "He possessed all the qualities which can make a man great, and Providence afforded him abundant opportunities of developing them. He gave proofs of prudence at an age when youth, in general, exhibits nothing but errors. He never abused the heroic virtues, but applied his valour to the defence of his dominions, and the assistance of his allies. He had a sound judgment, which made him a great statesman; and was active and affable, which made him a good sovereign. His soul was the seat of virtue; prosperity could not inflate, nor adversity depress it. He was the restorer of his country, the arbiter of his equals, and the founder of the power of Brandenburg. _His life was his panegyric._"