Horatio Hale (May 3, 1817 - December 28, 1896), American ethnologist, was born in Newport, New Hampshire.

He was the son of David Hale, a lawyer, and of Sarah Josepha Hale (1790-1879), a popular poet, who, besides editing Godey's Lady's Magazine for many years and publishing some ephemeral books, is supposed to have written the verses "Mary had a little lamb," and to have been the first to suggest the national observance of Thanksgiving Day.

The son graduated in 1837 at Harvard, and during 1838-1842 was philologist to the United States Exploring Expedition , which under Captain Charles Wilkes sailed around the world. Of the reports of that expedition Hale prepared the sixth volume, Ethnography and Philology (1846), which is said to have laid the foundations of the ethnography of Polynesia. He was admitted to the Chicago bar in 1855, and in the following year removed to Clinton, Ontario, Canada, where he practised his profession, and where on the 28th of December 1896 he died.

He made many valuable contributions to the science of ethnology, attracting attention particularly by his theory of the origin of the diversities of human languages and dialects--a theory suggested by his study of child-languages, or the languages invented by little children. He also emphasized the importance of languages as tests of mental capacity and as criteria for the classification of human groups. He was, moreover, the first to discover that the Tutelos of Virginia belonged to the Siouan family, and to identify the Cherokee as a member of the Iroquoian family of speech.

Besides writing numerous magazine articles, he read a number of valuable papers before learned societies. These include:

• Indian Migrations as Evidenced by Language (1882)
• The Origin of Languages and the Antiquity of Speaking Man (1886)
• The Development of Language (1888)
• Language as a Test of Mental Capacity: Being an Attempt to Demonstrate the True Basis of Anthropology (1891)

He also edited for Brinton's Library of Aboriginal Literature, the Iroquois Book of Rites (1883).