The Diocese of Kanjirapally was erected by His Holiness Pope Paul VI of illustrious memory, through the Bull "Nos Beati Petri Successores" on February 26, 1977 as a suffragan of the Archdiocese of Changancherry. On May 12, 1977, Archbishop Mar Antony Padiyara officially published the Papal Bull at St. Dominic's Cathedral, Kanjirapally and Mar Joseph Powathil, the then Auxiliary Bishop of the Archdiocese of Changanacherry was installed the First Bishop of Kanjirapally. Mar Joseph Powathil laid the foundation of the multifarious development activities - both spiritual and secular - in the diocese. When Mar Joseph Powathil was installed as the Archbishop of Changancherry in 1986, Mar Mathew Vattakkuzhy became the Episcopal torchbearer. Under his patronage the diocese witnessed spiritual renewal and acceleration in multi - faceted growth. In the event of his retirement in January 2001, Mar Mathew Arackal was appointed Bishop of Kanjirapally to pilot the diocese in the new millennium.

The diocese consists of 8 Deaneries within which there are 123 Parish churches and 38 Stations and Chapels for a Catholic population of 1,88,000. It mainly comprises the rural and the mountainous regions in the civil districts of Kottayam, Idduki and Pathanamthitta in the state of Kerala covering an area of 1980 sq. kms. This Catholic diocese forms part of the Syro - Malabar Major Archiepiscopal Church. Nilackal, one of the seven churches founded by St. Thomas, the Apostle in 52 A.D. is located in the eastern part of this diocese. The high ranges of this diocese are mostly covered with forests. The temperature in this region is comparatively low considering other parts of Kerala. The misty meadows and the green topography of this virgin forest create an atmosphere of serenity and a halo of sacredness. Most of the people who settled in high ranges are migrants from other parts of Kerala, who rely on agriculture for their livelihood. Ever since its inception the diocese has been engaged in the social and economic development of the people, together with its spiritual work. Accordingly the diocese implemented many schemes for these purposes and as a result, we have been able to provide a network of institutions to the people. Motivated by love, the diocese is striving day in and day out to bring the abundance of life to every one within her reach. By the Grace of God, the diocese had done commendable works to the spectrum of spiritual renewal and social and educational development of this region following the footsteps of the supreme shepherd Jesus Christ. Standing on the threshold of the Silver Jubilee year, the diocese of Kanjirapally is looking forward to an era of Grace in which she hopes to take giant strides in social, economic and spiritual amelioration.