The Onitsha Archdiocese, located in Anambra State, Nigeria, plays a significant role in serving a substantial population of Catholic faithful.  It was first erected as Prefecture Apostolic of Lower Niger {Niger Inferiore} on 25th July 1889.  The Prefecture covers the whole of Southern Nigeria and parts of Cameroun. It was later elevated to an Archdiocese on 18th April 1950.

Presently, the Archdiocese ministers to over 2,185,561 Catholics, with  136 parishes and is served by 498 priests. It is also supported by 718 religious individuals who fulfill various roles within the Catholic community.

In addition to its clergy and religious personnel, the Archdiocese is proud to have 137 senior seminarians in training. These individuals are the future leaders and spiritual guides for the Catholic community, and they play a crucial role in continuing the mission of the Church.

The Archdiocese extends its influence beyond the realm of worship and spirituality by operating several institutions, including schools, hospitals, and social welfare centers. These institutions provide vital services to the local community, encompassing education, healthcare, and social support.

Overall, the Onitsha Archdiocese is a central pillar in the lives of its Catholic population, providing both spiritual guidance and essential services that cater to the broader needs of the community in Anambra State, Nigeria.