This book is a grammar of Meskwaki, an Algonquian language spoken today in Tama County, Iowa. There are two factors that make Meskwaki of particular interest and importance. It is arguably the most archaic language of the Algonquian family in preserving the word shapes of the ancestral Algonquian language that is reconstructed as Proto-Algonquian by linguists. And it is documented by a very large collection of texts written by numerous native speakers more than a century ago that is kept in the National Anthropological Archives of the Smithsonian Institution. Meskwaki is a highly inflected language with extremely free word order. This grammar includes separate chapters on phonology (the sound system), grammatical categories, inflections, the derivation of stems, sentence structure, and some aspects of how sentences are connected to form longer utterances and narratives (discourse). The uses of the proximate and obviative third person categories are described and illustrated with numerous examples. The use of discontinuous compound words, phrases, and clauses is also described. Extensive reference is made throughout to the published and unpublished textual sources. An appendix lists and analyzes all the inflectional endings in the two long texts that have been published with interlinearized analysis, "The Autobiography of a Meskwaki Woman" and "The Owl Sacred Pack." Meskwaki is the heritage language of the Meskwaki Nation (the Sac and Fox Tribe of the Mississippi in Iowa).