Excerpts from Books and Wikipedia
"The meeting of Napoleon and Emperor Alexander I of Russia on a raft in the middle of the River Nemunas (Niemen) at Tilsit (Lithuania) in June 1807 marks the peak of the French ruler's power in Europe. Napoleon had defeated the Austrians at Austerlitz in 1805, the Prussians at Jena in 1806, and now he had just humiliated the Russian army at the battle of Friedland....Alexander agreed to the French remodeling of the states of Europe and agreed to join Napoleon's economic blockade of Britain. In return Napoleon would support Russian dealings with the Ottoman Empire. Two days later a further treaty was signed with Prussia, stripping her of half her territory and restricting her to an army of 100,000 men. Napoleon did not get all he wanted. . . . In this success lay the roots of future trouble. By humiliating Prussia, Napoleon created an implacable enemy. The economic blockade of Britain did not truly suit the Russians. Good relations did not last, and in 1812, Napoleon decided the only way to deal with Russia was through invasion and conquest." [1001 Days]