•
Ruth Manning-Sanders (1886–1988), poet and children's writer •
Ursula Masson (1945–2008), educator, literature researcher and non-fiction writer •
Gwerful Mechain (15th century), Welsh-language poet •
Nia Medi, since 2005, Welsh-language novelist and actress •
Dorothy Miles (1931–1993), poet, in English and sign language •
Moelona, pen name of Elizabeth Mary Jones (1877–1953), Welsh-language novelist, children's writer and translator •
Jan Morris (born James Morris, 1926–2020), Welsh historian and travel writer •
Ann Moray (1909–1981), novelist, short story writer and singer •
Elaine Morgan (1920–2013), non-fiction writer on anthropology, playwright and columnist •
Elena Puw Morgan (1900–1973), Welsh-language novelist and children's writer •
Elizabeth Morgan (born 1930), non-fiction writer •
Eluned Morgan (1870–1938), Welsh-language author from
Patagonia, travel writer and non-fiction writer •
Gwenllian Elizabeth Fanny Morgan (1852–1939), non-fiction writer and mayor •
Penelope Mortimer (1918–1999), journalist, biographer and novelist •
Wendy Mulford (born 1941), poet and feminist ==N==