In December 1935, when Bishop Joseph Shanahan arrived onitsha from Ireland to bless the edifice the newly built Cathedral that shanahan saw was heart stopping in its splendor. The basilica which was then the cathedral stands on elevated piece of land which is part of the 20 hectares made available for Fr. Lutz and his team by Obi Anazonwu and chiefs of Onitsha on 6 January 1886. Till 1930 what served as the central place of worship for the vicariate was the dual purpose building erected in 1914,the present holy Trinity primary school. The Holy Trinity cathedral was built between 1930 and 1935. In 1932, Bishop Shanahan handed over the mantle of leadership of the church to Bishop Charles Heerey on account of ill health especially the eyes. He retired and left for Ireland to allow the new Bishop a free hand. Shanahan was invited back for the jubilee and a major activity of the jubilee was the blessing of the cathedral. The cathedral like many other houses in Onitsha was battered during the Nigerian civil war. The post war reconstruction happened to collide with the early period of the recommendations of the Vatican ll council especially regarding the liturgy. So the church in Onitsha while repairing the damages to the Holy Trinity cathedral reconstructed it to be in tune with the new liturgy.