Robert Vaughn (born Robert Vaughan; June 5, 1836 — March 23, 1918) was a Welsh immigrant to the United States and an important rancher, farmer, and businessman in the U.S.
state of Montana before and after the early years of its statehood.
He homesteaded the Vaughn ranch in the Sun River valley in Montana, building a sandstone mansion as his home there.
The town of Vaughn, Montana, is named in his honor, and helped co-found the city of Great Falls, Montana.
He built the Arvon Block, a hotel and stable in Great Falls, one of the city's earliest buildings; the ranch and the hotel are both listed on the National Register of Historic Places.