Over an area of 11,928 sq. km., it has 623,756 inhabitants, of whom 620,000 are Catholics, distributed in 28 parishes, served by 45 diocesan priests and 16 religious, assisted by 7 male and 10 female religious communities; it has a provincial seminary (Our Lady of the Assumption) and a minor seminary; 41 educational institutes and 5 charitable and welfare works.
The diocese was created by the bull of Leo XIII *Postremis hisce temporibus* of 2 July 1900 under the name of Alagoas (comprising the entire State), detached from the archdiocese of Olinda and Recife; it in turn ceded (3 Apr. 1916) a group of parishes for the new diocese of Penedo; it changed its name to M. on 25 Aug. 1917; it was elevated to metropolitan status on 13 Feb. 1920. Its suffragan sees are Aracaju and Penedo.
The first bishop of the diocese was A. M. de Castilho-Brandão (d. 1910), the successor M. A. de Oliveira Lopes, who founded the newspaper *O Mensageiro de Fé* there and became its first archbishop.
The titular of the cathedral is Our Lady of Pleasures.