The eparchy of Kothamangalam was established in 1956 by Pope Pius XII, bifurcating the eparchy of Ernakulam.

The eparchy of Kothamangalam was established in 1956 by Pope Pius XII, bifurcating the eparchy of Ernakulam. The new eparchy included the foranes of Kothamangalam, Mailacombu and Arakuzha. Rt. Rev. Mgr. Mathew Pothanamuzhy was appointed the first bishop of the eparchy.Among the various pastoral activities faith formation was given prime importance. Rev. Fr. Varghese Mothakunnel was in charge of the catechetical activities. He divided the whole diocese into seven zones, viz., Kothamangalam, Arakuzha, Mailacombu, Muthalakodam, Karimannoor, Vazhakulam and Marika, to make the activities systematic and more effective. Faith education was given to students dividing them in to three groups, viz., Lower Primary, Upper Primary, and High School. A centralized system of conducting examinations was also adopted.