Madeleine L'Engle was an American writer of fiction, non-fiction, poetry, and young adult fiction, including A Wrinkle in Time and its sequels: A Wind in the Door, A Swiftly Tilting Planet, Many Waters, and An Acceptable Time. Her works reflect both her Christian faith and her strong interest in modern science.

Madeline Frank Brandeis was an American writer of children's books, a film producer and director.

Mohandas Karamchand Gandhi was an Indian lawyer, anti-colonial nationalist and political ethicist who employed nonviolent resistance to lead the successful campaign for India's independence from British rule. He inspired movements for civil rights and freedom across the world. The honorific Mahātmā, first applied to him in South Africa in 1914, is now used throughout the world.

Mary Josephine "Maisie" Ward Sheed, who published under the name Maisie Ward, was a writer, speaker, and publisher. Maisie's brother Leo Ward was co-founder of the publishing house Sheed and Ward; Maisie took his place when Leo left to become a priest.

Malcolm Routh Jameson, commonly known as Malcolm Jameson, was an American science fiction author. An officer in the US Navy, he was active in American pulp magazines during the Golden Age of Science Fiction. His writing career began when complications of throat cancer limited his activity. According to John W. Campbell Jr., Jameson "had much to do with the development of modern [c.1945] naval ordnance."

Manly Palmer Hall was a Canadian author, lecturer, astrologer, mystic and Freemason. Over his 70-year career he gave thousands of lectures and published over 150 volumes, of which the best known is The Secret Teachings of All Ages (1928). In 1934 he founded the Philosophical Research Society in Los Angeles.

Manly Wade Wellman was an American writer. While his science fiction and fantasy stories appeared in such pulps as Astounding Stories, Startling Stories, Unknown and Strange Stories, Wellman is best remembered as one of the most popular contributors to the legendary Weird Tales and for his fantasy and horror stories set in the Appalachian Mountains, which draw on the native folklore of that region. Karl Edward Wagner referred to him as "the dean of fantasy writers." Wellman also wrote in a wide variety of other genres, including historical fiction, detective fiction, western fiction, juvenile fiction, and non-fiction.

Manuel María del Pilar Eduardo de Gorostiza y Cepeda was a Mexican Spanish writer, dramatist and diplomat. He was the son of Pedro Fernández de Gorostiza, governor of the port of Veracruz, and the poet Rosario Cepeda. Gorostiza was in 1824 the first Mexican ambassador to the United Kingdom of the Netherlands. Later he was ambassador in London. Gorostiza was the Mexican envoy to the United States in 1836 with the mission to halt the support of Washington to Texas. As Mexican Minister of Foreign Affairs in 1838 and 1839 he had to deal with the Republic of Texas.

Manuel Tamayo y Baus (15 September 1829 – 20 June 1898) was a Spanish dramatist.

Marah Ellis Ryan, also known as Ellis Martin, was an author, actress, and activist from the United States. She was considered an authority on Native Americans after living with the Hopi.