Martin Wright Sampson was born on September 7, 1866, in Cincinnati, Ohio. He was the son of William S. Sampson and Virginia Ada (Wright) Sampson. He studied at the University of Cincinnati, earning his A.B. in 1888 and A.M. in 1890. He did graduate work in Germany, France, England, and Ireland, including study at the University of Munich in 1888. From 1889 to 1891, he was first instructor and then assistant professor of English at the University of Iowa. During the following year (1892), he taught at Stanford. For the next thirteen years, he was professor of English at Indiana University (1893-1906). Professor Sampson came to Cornell University in 1908 as acting professor of English, and soon became one of the most prominent members of the faculty. He became head of the English Department at Cornell in 1909 and was named Goldwin Smith Professor of English Literature in 1912 as well as an honorary member of the Class of 1912. He was a founder of the Manuscript Club, made up of young writers, and hosted the group at his home each Saturday evening during the school year. In 1919, he founded the Sampson Fine Arts Prize, given annually to a student who showed the most intelligent appreciation of the graphic and plastic arts and of photography. The award is still given annually to members of the senior class who have consistently demonstrated academic excellent, commitment, and achievement, particularly in the field of the history of art.

Professor Sampson edited a number of works in the field of English literature, notably the poems of Milton. He was well known for his original writings, including stories for children, plays, satires, and poetry. Professor Sampson was a joint author with E.O. Holland of a textbook entitled Written and Oral Composition (1907). He was a translator of Hans Wolfgang Singer’s Dresden 1: The Royal Picture Gallery (1907), an editor of numerous works, inlcuding The Lyric and Dramatic Poems of John Milton (1901), John Webster's The White Devil and the Duchess of Malfy (1904), Elizabeth Gaskell’s Cranford (1905), Selections from Irving’s Sketch-book (1907), Shakespeare’s Two Gentlemen of Verona (1912), Thomas Middleton (1915), Selections from John Milton (1925), and Henry James’ Daisy Miller (1927) and The Ambassadors (1930). The Good Giant, a series of stories for children, was published in 1928 from stories he wrote for his own four children. His attitude towards academic problems was entertainingly presented in a one-act satire, The Soul of a Professor (published in Cornell University Plays, 1932). A volume of his poems, Voices in the Forest, was published posthumously in 1933. He was frequently asked to read from his own writings and readings he held outside of Sibley Hall for engineering students eventually became a part of the curriculum for the Sibley College of Engineering. He was also a contributor to literary journals, a member of Phi Beta Kappa, Phi Kappa Sigma, and Quill and Dagger. He was a trustee of Wells College. In January of 1930, he began writing a column, “The Swinging Bridge,” for the Cornell Alumni News.

During World War I, Sampson was instrumental in establishing and raising funds for the Cornell unit of the American Ambulance Field Service. This group had the distinction of being the first to get to the front under the American flag. He edited Camion Letters from American College Man: Volunteer Divers of the American Field Service in France (1917) and just before his death, he completed editing Military Records of Cornell University in the World War (1930).

In 1892, Sampson married Frances Van Rensselaer Gardiner, who died in 1909. In 1910, he married his second wife Julia Dauchy Pattison of Troy, New York. They had four children together, Stephen Hastings, Martin Wright, Jr., Margaret Virginia, and Edward Coolidge. His son Martin Wright Sampson, Jr., would also go on to become a professor at Cornell University.