The wars in which Russia was engaged and the necessity of maintaining a large and well-equipped army, together with the increasing expenses of the Court, and above all, the dishonest practices of the officials rendered the burden of taxation so unbearable, that several revolts broke out. In 1648, the people of Moscow rose and demanded the surrender of a judge and another officer, both of whom were notoriously corrupt; the two men were promptly murdered. Then the popular fury turned upon Morozof, who would have suffered the same fate, had not the czar helped him to escape. The government was helpless. In some places, such as Pskof, Novgorod, and elsewhere, the streltsi joined the people, and Russia was for some time at the mercy of an enemy.

It was fortunate for Russia that just at that time, Poland had serious trouble at home. A Cossack, owner of a large estate, educated and brave, was ill-treated and imprisoned by a Polish landowner; and his little son was publicly whipped. He went to Warsaw and laid his complaint before the king. Vladislas told him plainly that the nobles were beyond his control; then, pointing to his sword, he asked if the Cossack could not help himself. The Cossack took the hint, went home, and when the Polish landowners tried to arrest him, he fled to the Khan of the Crimea, interested him in his cause and returned at the head of a Mussulman army. Lithuania rose in rebellion against Poland; the governors and nobles, and especially the priests of the Catholic Church, were hunted down, and those of the Greek Church took revenge for recent injuries and insults.

Vladislas died, and the Diet elected his brother John Casimir. He tried to reduce the very serious rebellion by promises, but there was too deep a hatred between the two churches. Meanwhile order had been restored in Russia, when the people of Lithuania wrote to the czar begging him to take them under his protection. Alexis convoked the Estates, told them that he had been insulted by Poland, and that the Poles were persecuting the members of the Greek Church. They declared in favor of war, and a boyard was sent to Kief to receive the oath of allegiance. The people were willing provided their liberties would be respected. This the czar promised. He declared that the privileges of the Assembly and of the towns would be maintained, that only natives would be employed in the administration and in taxation.

Poland was now sorely pressed. Charles X of Sweden invaded the kingdom and took two of its capitals. The Cossack and Lithuanians entered it from the south, and the Czar Alexis at the head of his own army attacked it on the east. He maintained strict discipline so that the Polish Governors said, "Moscow makes war in quite a new way, and conquers the people by the clemency and good-nature of the czar." The towns of White Russia opened their gates to his army, and Smolensk surrendered after a five weeks' siege. The Swedes captured Warsaw, the last capital of the misruled kingdom.

It was the jealousy of its enemies that saved Poland this time. Alexis entered into a truce and attacked Sweden. This war was carried on from 1656 until 1661, and ended by the peace of Cardis whereby neither country gained any advantage. The Poles, seeing the danger they had incurred, rallied, and once again war broke out with Russia. It was carried on with various success until both countries were exhausted. In 1661, a thirteen years' truce was concluded, whereby Russia restored Lithuania, but kept Little Russia on the left bank of the Dnieper, together with Kief and Smolensk.

In 1668, a revolt was organized by the Metropolitan of Kief, who preferred the jurisdiction of the Patriarch of Constantinople to that of Moscow. As a result, Little Russia was subject to all the horrors of war, but the Russian power prevailed in the end. Then the Cossacks of the Don broke out, and until 1671 the territory between that river and the Volga suffered terribly.

Alexis' reign was remarkable for the introduction of so-called "reforms" in the Church, which were confined wholly to ceremonies and externals. The czar supported the "reformer" Nicon, and those who did not agree with him were called religious madmen and suffered persecution. The monasteries near Archangel rebelled and troops were sent against them; but it was eight months before the sturdy monks capitulated.

Alexis continued his father's efforts to reëstablish intercourse with Western Europe. But the West was only recovering from the terrible Thirty Years' War, so that little interest was shown.

Alexis had married twice. From the first marriage he had two sons Feodor and Ivan, and six daughters; by his second wife he had one son, Peter, and two daughters. When he died, in 1676, he was succeeded by his eldest son Feodor.

Feodor Alexievitch, the third czar of the Romanof family, reigned only six years, from 1676 to 1682. It was under his reign that a truce for twenty years with Turkey, restored peace to White Russia.