Sheldon Peck was an American folk artist, conductor on the Underground Railroad, and social activist. Peck's portraiture – with its distinctive style — is a prime example of 19th century American folk art. He also become known for advocating abolitionism , racial equality, temperance, public education, women's rights, and pacifism.

Peck was born in Cornwall, Vermont, the ninth son of Jacob and Elizabeth Peck. Peck's ancestors helped found the New Haven Colony; his father worked as a blacksmith and served as a private in the Revolutionary War.

Peck married Harriet Corey (1806-1887) in 1825 and the couple eventually had thirteen children. The Peck family moved to Jordan, New York in 1828 and lived there until moving westward to Chicago in 1836. A year later Peck finally settled in Babcock's Grove (now Lombard) approximately twenty-five miles west of Chicago. On his 160 acres of farmland, Peck built a 1+1⁄2-story timber-frame house (completed in 1839) that still stands today. He grew crops and raised Merino sheep, the latter being a way to produce raw material for clothes without supporting the Southern-based cotton industry and its use of African slave labor. No records exist to indicate that Peck received any formal art education. His work may have been influenced by William Jennys, a primitive portrait painter who was active in Vermont around the time Peck lived there. Peck also would have had access to art instruction texts that were housed in the library of the Cornwall Young Gentleman's Society.

Peck died on March 19, 1869, survived by his wife and ten of his thirteen children. He is buried in the Lombard Cemetery. His youngest son, Frank, kept a diary which historians find very useful in documenting negro spirituals as well as the Underground Railroad.