Church growth can be internal, extension, and cross-cultural. Three critical areas to measure the viability of an ecclesiastical area are manpower, finance, and infrastructure. The Anglican diocese of Niger Delta North (DNDN) was inaugurated May 16, 1996 as the 53rd diocese in Church of Nigeria (Anglican Communion) with focus on missions and evangelism. To what extent has DNDN demonstrated viability especially in manpower development within twenty five years (1996-2021) of her mission work? The historical and descriptive methods were applied to unravel the task of this research. Data were collected from primary and secondary sources. The study revealed that Church of Nigeria (Anglican Communion) has harvested for the expansion of the work of God, thirteen bishops from DNDN within twenty-five years of her mission enterprise. Three were to shepherd the diocese, five lead extension dioceses which were birthed by DNDN, and another five for cross-cultural dioceses. Among these, two have been elevated to the apex ecclesiastical leadership position of an Archbishop. Thus, DNDN is a good ground for harvesting leaders for missions and evangelism in Nigeria and beyond. Downsizing DNDN rather than weaken her viability as some had feared, has increased her fruitfulness, growth and relevance to the community. These developments can be sustained and expanded through systematic teachings and intentional discipleship. Partnership with the extension and cross-cultural bishops and their dioceses are needed in church planting, human and material development. Further study on the inter-relationship between these dioceses will enrich Nigerian ecclesiastical history.