The Court of Versailles, in this peril, looked to Frederic for help. He had been guilty of two great treasons: perhaps he might be induced to commit a third. The Duchess of Chateauroux then held the chief influence over the feeble Lewis. She, determined to send an agent to Berlin; and Voltaire was selected for the mission. He eagerly undertook the task; for, while his literary fame filled all Europe, he was troubled with a childish craving for political distinction. He was vain, and not without reason, of his address, and of his insinuating eloquence: and he flattered himself that he possessed boundless influence over the King of Prussia. The truth was that he knew, as yet, only one corner of Frederic's character. He was well acquainted with all the petty vanities and affectations of the poetaster; but was not aware that these foibles were united with all the talents and vices which lead to success in active life, and that the unlucky versifier who pestered him with reams of middling Alexandrines, was the most vigilant, suspicious, and severe of politicians.
Voltaire was received with every mark of respect and friendship, was lodged in the palace, and had a seat daily at the royal table. The negotiation was of an extraordinary description.
Nothing can be conceived more whimsical than the conferences which took place between the first literary man and the first practical man of the age, whom a strange weakness had induced to exchange their parts. The great poet would talk of nothing but treaties and guarantees, and the great King of nothing but metaphors and rhymes. On one occasion Voltaire put into his Majesty's hands a paper on the state of Europe, and received it back with verses scrawled on the margin. In secret they both laughed at each other. Voltaire did not spare the King's poems; and the King has left on record his opinion of Voltaire's diplomacy. "He had no credentials," says Frederic, "and the whole mission was a joke, a mere farce."
But what the influence of Voltaire could not effect, the rapid progress of the Austrian arms effected. If it should be in the power of Maria Theresa and George the Second to dictate terms of peace to France, what chance was there that Prussia would long retain Silesia? Frederic's conscience told him that he had acted perfidiously and inhumanly towards the Queen of Hungary. That her resentment was strong she had given ample proof; and of her respect for treaties he judged by his own. Guarantees, he said, were mere filigree, pretty to look at, but too brittle to bear the slightest pressure. He thought it his safest course to ally himself closely to France, and again to attack the Empress Queen.
Accordingly, in the autumn of 1744, without notice, without any decent pretext, he recommenced hostilities, marched through the electorate of Saxony without troubling himself about the permission of the Elector, invaded Bohemia, took Prague, and even menaced Vienna.
It was now that, for the first time, he experienced the inconstancy of fortune. An Austrian army under Charles of Lorraine threatened his communications with Silesia. Saxony was all in arms behind him. He found it necessary to save himself by a retreat. He afterwards owned that his failure was the natural effect of his own blunders. No general, he said, had ever committed greater faults. It must be added, that to the reverses of this campaign he always ascribed his subsequent successes. It was in the midst of difficulty and disgrace that he caught the first clear glimpse of the principles of the military art.
The memorable year 1745 followed. The war raged by sea and land, in Italy, in Germany, and in Flanders; and even England, after many years of profound internal quiet, saw, for the last time, hostile armies set in battle array against each other. This year is memorable in the life of Frederic, as the date at which his noviciate in the art of war may be said to have terminated. There have been great captains whose precocious and self-taught military skill resembled intuition. Conde, Clive, and Napoleon are examples. But Frederic was not one of these brilliant portents. His proficiency in military science was simply the proficiency which a man of vigorous faculties makes in any science to which he applies his mind with earnestness and industry. It was at Hohenfriedberg that he first proved how much he had profited by his errors, and by their consequences. His victory on that day was chiefly due to his skilful dispositions, and convinced Europe that the prince who, a few years before, had stood aghast in the rout of Molwitz, had attained in the military art a mastery equalled by none of his contemporaries, or equalled by Saxe alone. The victory of Hohenfriedberg was speedily followed by that of Sorr.
In the meantime, the arms of France had been victorious in the Low Countries. Frederic had no longer reason to fear that Maria Theresa would be able to give law to Europe, and he began to meditate a fourth breach of his engagements. The Court of Versailles was alarmed and mortified. A letter of earnest expostulation, in the handwriting of Lewis, was sent to Berlin; but in vain. In the autumn of 1745, Frederic made Peace with England, and, before the close of the year, with Austria also.
The pretensions of Charles of Bavaria could present no obstacle to an accommodation. That unhappy Prince was no more; and Francis of Lorraine, the husband of Maria Theresa, was raised, with the general assent of the Germanic body, to the Imperial throne.