Charles William Eliot was the Harvard President from 1869 to 1909. He was an American academic who revolutionized the curriculum and academic structure of Harvard University. He was a renowned chemist, educator, and scholar who served as the president of Harvard for 40 years, making him the longest-serving president in the university's history. He is credited with modernizing the university and introducing elective courses, which allowed students to pursue their own interests. He also established the first graduate school in the United States and introduced the system of awarding Ph.D. degrees. Eliot's tenure as president of Harvard was marked by significant growth and expansion of the university.