The Mission as a Frontier Institution in the Spanish-American Colonies is the famous 1917 essay by Herbert Eugene Bolton (1870-1953), published in the American Historical Review. Bolton, the Berkeley historian who invented the study of the Spanish Borderlands, argues here that the mission was Spain’s distinctive frontier agency, doing the work that forts and trading posts did for other empires. The essay reoriented American colonial history beyond the thirteen colonies and is still assigned a century later. Free PDF download available on BDeBooks.