[3] He went on to study at Harvard Divinity School, where his classmates included Thomas Wentworth Higginson and Samuel Johnson, with whom he would later collaborate in his hymn writing.

He is considered part of the second-generation of transcendentalists;[4] after becoming a Unitarian pastor, he adapted the transcendental philosophy he had encountered in divinity school into his hymns and sermons.

Longfellow served as a gym leader in Fall River, Massachusetts (1848), Brooklyn's Second Unitarian Church (1853), and Germantown, Pennsylvania (1878-1882).

[8] Throughout his life Longfellow had romantic friendships with men, and struggled with his sexuality, writing in 1837 of one such companion, William Winter: "I don’t think I have made a greater sacrifice of inclination to a sense of duty - but not a hearty one - I was reluctant then; I have been sorry at times ever since.

"[8] In 1842 he met fellow Divinity student Samuel Johnson: of their long association, a friend wrote: "There existed for forty years an intimacy which could hardly have been understood by David and Jonathan.”[9] Longfellow later served a friend and mentor to young men such as Morton Fullerton.