Between 1890 and 1920 the US Army underwent profound changes in organization, function, composition and appearance. The Army was transformed from a small, blue-clad force whose primary weapon was the single-shot rifle, into a mighty host of men dressed in dirt-coloured combat uniforms, using automatic weapons, tanks and aircraft to fight enemies on fields across the world. This book details the Army's developments during its involvement in the Spanish-American War (1898), the Boxer Rebellion (1898-1901), and World War I (1914-1918). Particular attention is given to the evolution of the Army's uniforms, which are illustrated vividly throughout the book.