Tambor de Mina is the Afro-Maranhão religious tradition — the local variant of the broader Afro-Brazilian spiritual complex that includes Candomblé, Umbanda, and related practices. São Luís has been its spiritual centre since the 19th century, when enslaved Africans from the Fon and Yoruba peoples established the first terreiros here.
The tradition involves ceremonial drumming, spirit possession, and intricate ritual practices passed down through unbroken lineages since the colonial period. If you have a genuine interest in Afro-Brazilian religion, São Luís is the place to pursue it — the city's terreiros are more accessible and more welcoming to respectful outsiders than those of Bahia. Ask at the Centro de Cultura Popular for contacts and guidance.