[4] His doctoral dissertation is titled The Express and Stagecoach Business in California, 1848–60.
[6] After receiving his Ph.D., Winther held visiting positions at Stanford University and the San Jose Adult Education Center.
[5] From 1936 to 1937 he was an assistant curator of the Wells Fargo Bank and Union Trust Company Museum in San Francisco.
His core interest, as represented by Express and Stagecoach Days in California (1936) and The Transportation Frontier: Trans-Mississippi West, 1865-1890 (1964), was nineteenth-century western transportation, particularly the ways in which stagecoaches, wagon trails, railroads, and steamships shaped the economy and society of the U.S. West.
[8] In 1970 the Western History Association Council established the Oscar O. Winther award given each academic year in recognition of the peer-reviewed article judged to be the best published for that past year in the Western Historical Quarterly.