"Thomas Hart Benton" by Theodore Roosevelt is a historical account written in the late 19th century. The book explores the life and contributions of Thomas Hart Benton, a significant political figure and senator from Missouri during a transformative period in American history, particularly focusing on the expansionist ethos of the United States. The opening of the work introduces the context of the early Western United States, outlining the fervent movement of pioneers westward after the Revolutionary War and the characteristics of the burgeoning states in the Mississippi basin, such as Kentucky and Tennessee. It emphasizes how these adventurous frontiersmen, forged from diverse backgrounds yet unified by their pioneering spirit, laid the groundwork for a burgeoning America. Roosevelt frames Benton as both a product of and a vital player in this formative era, detailing his early life and political entry against the backdrop of a rapidly changing nation grappling with issues of frontier settlement, governance, and identity. (This is an automatically generated summary.)