Born in Baltimore, Charles attended Harvard Divinity School after graduating in 1840 from Harvard College, along with Henry David Thoreau. After serving as a minister-at-large in St. Louis, Baltimore, and Portsmouth, New Hampshire, he became "the first and only American Unitarian foreign missionary."

Dall then ministered on behalf of the American Unitarian Association in Calcutta, India from 1855 until his death in 1886. His work with Hindu social and religious reformers, Ram Mohan Roay and Keshab Chandra Sen, led to their joining Unitarianism and his joining the Hindu society. American and Indian traditions were mutually affirmed. This historic period has been termed the Bengal Renaissance of the nineteenth century. See Unitarians in India by Spencer Lavan (Boston: Beacon Press, 1977).