St. Joseph's functions as the cathedral of the Archdiocese of Baghdad (Bagdathensis Latinorum) which was established in 1643 as a diocese and elevated to its present status in 1848.

During World War II, Polish troops stationed in Baghdad in 1942 and 1943 celebrated Divine Liturgy in the cathedral along with the bishops.

[5] In recent years, the cathedral is suffering from neglect due to government oversight and is in dire need of restoration.

[5] The cathedral is built in Iraqi architecture and uses traditional bricks that were used in Iraq to build structures, including both mosques and churches.

The churchyard contains a graveyard that includes the tombs of the Carmelite fathers, the founders of the Church, as well as graves of monks and nuns.