Theodore Roosevelt Jr. (1858 - 1919) was an American statesman, author, explorer, soldier, naturalist and reformer who served as the 26th president of the United States from 1901 to 1909. As a leader of the Republican Party during this time, he became a driving force for the Progressive Era in the United States in the early 20th century. Roosevelt was mostly home schooled by tutors and his parents. Biographer H. W. Brands argues that "The most obvious drawback to the home schooling Roosevelt received was uneven coverage of the various areas of human knowledge". He was solid in geography (as a result of self study during travels) and bright in history, biology, French and German; however, he struggled in mathematics and the classical languages. He entered Harvard College on September 27, 1876; his father told him "Take care of your morals first, your health next, and finally your studies".