Martti Haavio, Finnish poet and mythologist (d. 1973)
Martti Henrikki Haavio (22 January 1899 – 4 February 1973) was a Finnish poet, folklorist and mythologist, writing poetry under the pen name P. Mustapää. He was born on 22 January 1899 in Temmes, and died 4 February 1973 in Helsinki. He was also a professor of folklore and an influential researcher of Finnish mythology. In 1960, Haavio married Aale Tynni, after his first wife Elsa Enäjärvi-Haavio died in 1951 of cancer. His daughter, Elina Haavio-Mannila, is a social scientist. During Haavio's early career, he was a member of the Tulenkantajat literature club.

He is buried in the Hietaniemi Cemetery in Helsinki.