The history of Russia is full of mysteries. One of them is connected with the Prut campaign. This campaign, which Peter I launched in an effort to achieve lightning success in the war with the Turks, is usually discussed as a tragedy. But is this really so? Why did the tsar consider the Wallachian ruler Brancoveanu to be the savior of the Russian army, while historians labeled him a “traitor”? And why did Peter I, assigning secondary importance to the Baltic problem, manage to defeat the “most invincible” army of the Swedes, “open a window to Europe,” but could not defeat the Turks? The author of the book, the famous historian E.V. Belova, writes about who formed the new policy against Ottoman and Tatar aggression, and also debunks myths and provides evidence of the falsification of a number of legends about the Prut campaign.