Nathan Clifford Ricker, D.Arch (June 24, 1843 – March 19, 1924) was a professor and architect known for his work at the University of Illinois. He was born on a farm near Acton, Maine June 24, 1843. In 1875, he was married to Mary Carter Steele of Galesburg, Illinois. Mary Steele graduated with honors from the University of Illinois in 1875. His only child, Ethel, was born in 1883. He died March 19, 1924.