Theodore "Teddy" Roosevelt was the 26th President of the United States, serving from 1901 to 1909. He was known for his energetic personality and progressive policies, which included trust-busting to regulate large corporations and the establishment of national parks to conserve natural resources. Roosevelt was a key figure in the Progressive Era, advocating for social reforms and labor rights. Before his presidency, Roosevelt was a soldier, author, and the Governor of New York. He was also a leader of the Rough Riders, a volunteer cavalry regiment during the Spanish-American War. His legacy includes the construction of the Panama Canal and the promotion of the Square Deal policy, which aimed to ensure fairness for all Americans.