Tsar Alexander I was the Emperor of Russia from 1801 to 1825. He was born on December 23, 1777, and became known for his role in the Napoleonic Wars. Alexander initially allied with Napoleon Bonaparte but later turned against him, leading a coalition of European powers to defeat Napoleon in 1814. During his reign, Alexander I implemented several reforms aimed at modernizing Russia, including educational and administrative changes. He was also a key figure in the Congress of Vienna, which sought to restore stability in Europe after the fall of Napoleon. Alexander died on December 1, 1825.