While on a (*)  raft in the middle of the Niemen River, he agreed to a treaty with a man he'd soon fight the Patriotic War against.
During this man's reign, a series of agricultural-military colonies where peasants were overseen by soldiers modeled on Aleksei Arakcheev's  (ah-rock-CHAY-eff's)  Gruzino  (GROO-zee-nuh)  estate were founded. A popular legend holds that this emperor, who died in faraway Taganrog, faked his own death and lived as a hermit named Feodor Kuzmich. His younger brother, the Grand Duke Constantine, was supposed to succeed this king, who convinced other European powers to join his Holy Alliance. While on a (*)  raft in the middle of the Niemen River, he agreed to a treaty with a man he'd soon fight the Patriotic War against. This Russian emperor agreed to the Treaty of Tilsit. The Battle of Borodino was fought during his reign. For 10 points, name this Russian emperor who withstood the invasion of his country by Napoleon.
During this man's reign, a series of agricultural-military colonies where peasants were overseen by soldiers modeled on Aleksei Arakcheev's  (ah-rock-CHAY-eff's)  
  Alexander I  [or  Alexander Pavlovich ; prompt on  Alexander ]