Frederick H. Billings was an American lawyer, financier, and politician. He is known for his legal work on land claims during the early years of California's statehood and his presidency of the Northern Pacific Railway from 1879 to 1881.

George Perkins Marsh, an American diplomat and philologist, is considered by some to be America's first environmentalist and by recognizing the irreversible impact of man's actions on the earth, a precursor to the sustainability concept, although "conservationist" would be more accurate. The Marsh-Billings-Rockefeller National Historical Park in Vermont takes its name, in part, from Marsh. His 1864 book Man and Nature had a great impact in many parts of the world.