Thomas Alexander was one of two men on whom the history of Forsyth depended heavily, alongside Hiram Marcyes, and he was dedicated to creative and aggressive growth. He began as a pioneer sheep, cattle, and horse rancher and prospector, also clerked at Fort Keogh, and fought with General Howard. He became a County Commissioner of the newly founded Rosebud County in 1901. By that time he was operating a general store, organized the first bank in Forsyth, Merchants National Bank, and housed it in a unique stone building made from stone quarried near Forsyth. He built the American Hotel, erected a town hall, built several large homes, and provided the land for the Northern Pacific Railroad Station. At the same time, he developed prosperous ranches. He belonged to the Odd Fellows, the Elks, and the Knights of Pythias, served on the early School Board, and Alexander School was named for him. Progressive Men of Montana regarded him as one of Rosebud County's leading and most representative citizens.