Paul III., her nephew, who succeeded the empress, detested Maria Theresa, and often inveighed bitterly against her haughtiness and her ambition.  On the contrary, he admired the King of Prussia.  He had visited the court of Berlin, where he had been received with marked attention; and Frederic was his model of a hero.  He had watched with enthusiastic admiration the fortitude and military prowess of the Prussian king, and had even sent to him many messages of sympathy, and had communicated to him secrets of the cabinet and their plans of operation.  Now, enthroned as Emperor of Russia, without reserve he avowed his attachment to Frederic, and ordered his troops to abstain from hostilities, and to quit the Austrian army.  At the same time he sent a minister to Berlin to conclude an alliance with the hero he so greatly admired.  He even asked for himself a position in the Prussian army as lieutenant under Frederic.

The Swedish court was so intimately allied with that of St. Petersburg, that the cabinet of Stockholm also withdrew from the Austrian alliance, and thus Maria Theresa, at a blow, lost two of her most efficient allies.  The King of Prussia rose immediately from his despondency, and the whole kingdom shared in his exultation and his joy.  The Prussian troops, in conjunction with the Russians, were now superior to the Austrians, and were prepared to assume the offensive.  But again Providence interposed.  A conspiracy was formed against the Russian emperor, headed by his wife whom he had treated with great brutality, and Paul III. lost both his crown and his life, in July 1762, after a reign of less than six months.

Catharine II., wife of Paul III., with a bloody hand took the crown from the brow of her murdered husband and placed it upon her own head.  She immediately dissolved the Prussian alliance, declared Frederic an enemy to the Prussian name, and ordered her troops, in cooeperation with those of Austria, to resume hostilities against Frederic.  It was an instantaneous change, confounding all the projects of man.  The energetic Prussian king, before the Russian troops had time so to change their positions as to cooeperate with the Austrians, assailed the troops of Maria Theresa with such impetuosity as to drive them out of Silesia.  Pursuing his advantage Frederic overran Saxony, and then turning into Bohemia, drove the Austrians before him to the walls of Prague.  Influenced by these disasters and other considerations, Catharine decided to retire from the contest.  At the same time the Turks, excited by Frederic, commenced anew their invasion of Hungary.  Maria Theresa was in dismay.  Her money was gone.  Her allies were dropping from her.  The Turks were advancing triumphantly up the Danube, and Frederic was enriching himself with the spoils of Saxony and Bohemia.  Influenced by these considerations she made overtures for peace, consenting to renounce Silesia, for the recovery of which province she had in vain caused Europe to be desolated with blood for so many years.  A treaty of peace was soon signed, Frederic agreeing to evacuate Saxony; and thus terminated the bloody Seven Years’ War.