Shimun XII Yoalaha

Mar Shimun XII Yoalaha was the seventh Patriarch of the Chaldean Catholic Church, from 1656 to 1662.

He succeeded Patriarch Shimun XI Eshuyow, the seat of the patriarchate of Babylon of the Chaldean Catholic church being in Khosrau-Abad near Salmas, Safavid Empire during his reign.

Mar Shimun XII Yoalaha like his predecessors Shimun X Eliyah and Shimun XI Eshuyow was not formally recognized by Rome after the hereditary Shimun line of Patriarchs was reintroduced by Patriarch Shimun IX Dinkha in the Chaldean church. Hereditary succession is an unacceptable practice in Catholic Church.

His successor in 1662 was Shimun XIII Dinkha, the last of the Shimun line in the Chaldean Church.