Austria was becoming alarmed at Russia's victories, and lent a willing ear to the suggestion of Frederick the Great that it would be safer to permit Russia to gain territory belonging to Poland, provided Austria and Prussia should receive their share. On February 17, 1771, a treaty was concluded between Russia and Prussia, and accepted by Austria in April, whereby Poland was deprived of a good part of its territory. Catherine, secured White Russia with a population of 1,600,000; Frederick the Great took West Prussia with 900,000 inhabitants, and Austria received Western Gallicia and Red Russia with 2,500,000 people. This was the beginning of the end of Poland.

The peace negotiations with Turkey were broken off, and war was resumed. Being busy elsewhere, Catherine could not prevent a coup d'état in Sweden, which saved that country from the fate of Poland. Besides suffering from these constant wars, Russia was visited by the plague, which in July and August, 1771, daily carried off a thousand victims in Moscow alone. The Archbishop, an enlightened man, was put to death by a mob for ordering the streets to be fumigated. Troops were necessary to restore order.

The condition of the country was dreadful. Alexander Bibikof was sent to suppress a dangerous insurrection, he wrote to his wife after arriving on the spot, that the general discontent was frightful. It was for this reason that Catherine concluded peace with the sultan in 1774; besides an indemnity, she received Azof on the Don and all the strong places in the Crimea, and was recognized as the protector of the sultan's Christian subjects. In 1775, she finally broke the power of the Cossacks.

Through the mediation of France and Russia, a war between Prussia and Austria concerning the succession in Bavaria, was narrowly averted. During the American War of Independence, Russia, Sweden, Denmark, Prussia, and Portugal, proclaimed armed neutrality, and Holland declared war, because British warships caused endless trouble to vessels under neutral flags. This celebrated act declared "that contraband goods" included only arms and ammunition. Most countries agreed to this, with the exception of England.

In 1775 Catherine annexed the Crimea, on the plea that anarchy prevailed. Turkey protested and threatened war but France meditated and the sultan recognized the annexation by the Treaty of Constantinople in 1783.

In 1787, a remarkable secret agreement was signed between Russia and Austria. It is known as the Greek Project, and was nothing less than a scheme to divide Turkey between the two powers. The plot as proposed by Russia, was to create an independent state under the name of Dacia, to embrace Moldavia, Wallachia, and Bessarabia, with a prince belonging to the Greek Church at the head. Russia was to receive Otchakof, the shore between the Bug and the Dnieper, and some islands in the Archipelago, and Austria would annex the Turkish province adjoining its territory. If the Turk should be expelled from Europe, the old Byzantine Empire was to be reëstablished, and the throne occupied by Catherine's grandson Constantine, "who would renounce all his claims to Russia, so that the two empires might never be united under the same scepter." Austria agreed on condition that she should also receive the Venetian possessions in Moldavia, when Venice would be indemnified by part of Greece.

Soon after this the sultan declared war against Russia. This took Catherine by surprise. Other enemies sprang up: the King of Prussia wanted Dantzig, the King of Sweden, South Finland. The latter invaded Russia and might have marched upon St. Petersburg, for all Catherine could collect was an army of 12,000 men. A mutiny in the camp of Gustavus III, compelled him to return to Stockholm, and the opportunity was lost. He defeated the Russians in the naval battle of Svenska Sund, but a second engagement was to the advantage of Russia. The French Revolution caused him to make peace, and to enter into an alliance with Russia against the French.

In the south Russian arms were more fortunate. The Turks were defeated in 1789, and 1790, on which occasions a young general named Souvorof distinguished himself. Upon the death of Joseph II of Austria, his successor Leopold made peace with Turkey at Sistova. (1791.) It was the French revolution, which seriously alarmed every crowned head in Europe, and which induced Catherine to follow Leopold's example at Jassy, in January, 1792, Russia kept only Otchakof and the shore between the Bug and the Dniester.

Poland, meanwhile, had made an earnest effort at reform. Thaddeus Kosciusko had returned from the United States, where he had fought for liberty and was trying to save his own country. Born in 1752, he entered a military school founded by the Czartoryskis at the age of twelve, and distinguished himself by attention to his studies and duties. His father was assassinated by exasperated peasants, and he himself was scornfully ejected by a powerful noble whose daughter he was courting. Attracted by the struggle of a handful of colonists against powerful England, he went to America and served with distinction in the War of the Revolution. After seeing Great Britain humbled and a new republic established in the New World, he came back to Poland and was soon among the foremost reformers,—a man in whom the patriotic Poles justly trusted. But traitors were found to accept Russian bribes, and for the second time Poland was despoiled. Russia annexed the eastern provinces with 3,000,000 inhabitants, and Prussia took Dantzig and Thorn. Austria was told that she might take from the French Republic as much as she wished,—or could.

Manfully and indefatigably did Kosciusko labor to stem the tide of his country's ruin. His patriotism aroused even that of the poor, down-trodden serfs, who had no interests to defend, yet stood by him in battle when the nobles on horseback fled, and wrenched a victory out of defeat. Well might Kosciusko thereafter dress in the garb of a peasant; a gentleman's dress was a badge of dishonor.