The 1st of January 1813, the Russian armies crossed Neman and soon reached Vistula and Oder. In February Prussia joined Russia, in April the forces of allies were on Elba. In May Napoleon who collected a new army, repulsed the allies to Oder. In July, the forces of the coalition increased because of the unification with Austria and German princedoms. But in the battle near Dresden (the 14th -15th of August), Napoleon turned into flight his opponent possessing a numerical superiority.
The 4th -6th of October in "fight of peoples" near Leipzig (220 thousand allies, 175 thousand French) the army of Napoleon was broken. Losses reached 65 thousand in the French army and 54 thousand in army of coalition.
The 19th of March 1814, after a number of bloody battles, the allied army with the 6th anti-French coalition (England, Russia, Austria and Prussia) entered Paris. Napoleon abdicated and was banished to Elba Island in the Mediterranean sea.
The congress of allied forces took place in September 1814 and June 1815 in Vienna. Serious contradictions between them caused a long secret struggle. News about flight of Napoleon to Elba and the temporary capture of the power by him in France ("Hundred days") unexpectedly sped up the achievement of the consent. Under the final act of the Viennese congress (the 28th of May 1815) Russia received Finland, Bessarabia and the territory of the former duchy of the Warsaw Empire called the Polish kingdom, unified with Russia through a dynastic union. The 6th of June 1815, Napoleon was broken in Waterloo by the incorporated forces of allies and banished for life at the Island St Elena in the Atlantic ocean.
For the maintenance of the new European order under Alexander's I initiative Russia, Austria and Prussia concluded the 14th of September 1815 Sacred Union, proclaiming the unification of Christian monarchies and their citizens. The recognition of the firmness of existing European monarchy was the basis of the union. Soon the Sacred union was adjoined almost by all European governors (England, Vatican and Turkey) were the exception due to the formal order). At meetings and congresses of the Sacred union in Aachen (1818), Тroppau and Laibakhe (1820-1821), Vienna and Verona (1822), decisions were taken, allowing managing with the revolutionary wave, which swept on Europe. The force of weapons suppressed the revolutions in Italy and Spain.
Trying to strengthen its influence in the East, Russia wanted to use the Sacred union for the support of Slavic people and Greeks in their struggle against the Muslim Turkey, but it was counteracted by England and Austria. The situation aggravated in the spring 1821 with the beginning of the Greek revolt under A.Ipsilanti , an officer of the Russian army. From fear to weaken the Union, Alexander I did not dare to assist insurgents, but in July 1821 he broke off diplomatic relations with Turkey.