sentences:  The Montana Southern Railway was largely the brainchild of William R. Allen, a politician and entrepreneur who had served as the lieutenant governor of Montana between 1909 and 1913.Allen was the president of the Boston-Montana Mining Company, which was developing a large silver-mining operation in the remote Pioneer Mountains of far southwestern Montana.Because of the site's remoteness and poor access, a railroad was considered to be a necessary component of the mining district's development.