What four US presidents won the Nobel Peace Prize?

Four U.S. presidents have won the Nobel Peace Prize: Theodore Roosevelt in 1906 for mediating the end of the Russo-Japanese War, Woodrow Wilson in 1919 for his role in establishing the League of Nations, Jimmy Carter in 2002 for his decades of peace efforts and humanitarian work, and Barack Obama in 2009 for his extraordinary efforts to strengthen international diplomacy and cooperation. These awards recognize their contributions to peace and conflict resolution on a global scale.