Asonbona was initially a Mass Centre of Baromasia. When Ratanpur was separated from Baromasia in 2005, Karlo-Asonbona became a sub-station of Ratanpur. Asanbona is located in the Rajmahal hills. The inhabitance of this place are mostly Paharias and Santhals. Late Rev.Fr. Thomas Kurungat, then Vicar General of the diocese, had initiated the educational and pastoral activities in Asanbona. Later, Rev. Fr. N. M. Thomas, then Priest In-charge built a magnificient church was inaugurated by Rt. Rev Kurien Valiakandathil on April 27, 2017.The distance from Ratanpur to Karlo-Asonbona is about 18 Kms and this place is located in Boarijore Block, Godda District. The parish consists of 18 villages and the total population of Catholics are 620. The Sisters of Don Bosco render their service in this area.