Morgan, Lewis Henry, 1818–81, American anthropologist, b. Aurora, N.Y., grad. Union College, Schenectady, 1840. Practicing as a lawyer, he became interested in the Native Americans of his locality, and in 1847 he was made an adopted member of the Seneca tribe. His League of the Ho-de-no-sau-nee or Iroquois (1851, repr. 1954) is unexcelled among early descriptive reports. Morgan was interested in social organization, and developed a theory correlating kinship terminologies with forms of marriage and rules of descent, holding that matriarchal patterns had originally prevailed over all other kinship patterns. His Systems of Consanguinity and Affinity of the Human Family (1870) presents this principle. Ancient Society (1877, repr. 1959), which classified the cultures of the world into progressive stages—savagery, barbarism, and civilization—attracted the attention of Marx and Engels, who interpreted its evolutionary doctrine as support for their materialistic theory of history. Morgan's work was accused of being overly speculative, and provoked a reaction against theories of cultural evolution within American anthropology that lasted well into 20th cent. Ethnographic and archaeological research has invalidated Morgan's specific evolutionary models, but his tireless research and his wide-ranging theoretical interests are credited with serving to advance the new field of anthropology. Morgan's Indian Journals were edited by Leslie A. White and published in 1959.
See biographies by B. J. Stern (1931, repr. 1967) and C. Resek (1960); study by T. R. Trautman (1987).