After its first bid for statehood was vetoed by President Andrew Johnson, Colorado entered the Union on August 1, 1876, the year the United States celebrated its centennial. Thus, the thirty-eighth state is known as the Centennial State. Among the early inhabitants of the land encompassed by Colorado were the Anasazi cliff dwellers. They were forced by drought and other factors to abandon their Mesa Verde homes in the late 1200s. At the ti...