Samuel Calvin was born February 2, 1840, in Wigtownshire, Scotland. Calvin's parents immigrated to the United States in 1851, and lived first in New York, and then moved to Iowa in 1855. On April 30, 1864, he enlisted in the service of the Union Army, 44th Regiment of the Iowa Infantry Volunteers, as a private in Company C, for a period of 100 days. At the time of his enlistment, Mr. Calvin was working as a carpenter. On September 5, 1865, he married Mary Louise Jackson of Hopkinton, Iowa. They had one child, Alice, born in 1866.

Calvin took his M.A. degree at Cornell College in 1874, and his Ph.D. at Lenox College in 1888. He received the LL.D. degree at Cornell College in 1904. He was professor of Natural Sciences at Lenox College in Hopkinton from 1864 to 1869, and served as the principal of a Dubuque, Iowa school from 1869 until 1873.

Calvin joined the faculty of the State University of Iowa in January 1874 as professor of Natural Science and curator of the University Cabinet. He was the first head of the SUI Geology Department, and served as geologist for the state of Iowa, with his focus on paleontology. His other areas of research and instruction were zoology and botany. In addition, he had a keen interest in environmental conservation, and was an accomplished photographer. Calvin made photographs of geological formations, as well as the architecture and people of the Iowa City area. Samuel Calvin died April 17, 1911.