During the Slum Clearance programme of the 1950's and early 1960's, whole communities were removed from the areas where they lived to the new housing estates being built on the outskirts of the town. Nunsthorpe, begun before the war but expanded rapidly in the post-war years. It soon became evident that St. Martin's church was too small to cater for everyone in what was then the largest housing estate in the town, so the community, formerly residents of King Edward Street and the surrounding area, and parishioners of St. Barnabas' Church, decided to build their own church.

In 1960 St. Mark's was dedicated, having been named after the nephew of St. Barnabas, the Apostle appointed to replace Judas Iscariot