Cheongju diocese covers a land area of 5,767 square kilometers, the whole Chungcheongbuk-do province, except Jecheon city and Danyang-gun county, which belong to Wonju diocese.
Cheongju diocese was originally an apostolic vicariate carved out from Seoul archdiocese on June 23, 1958. Before that, Seoul diocese was entrusted the Maryknoll Fathers and Brothers to serve the region from 1953 to 1958. On March 10, 1962, the Cheongju apostolic vicariate became a suffragan diocese of Daegu metropolitan. At of the end of 2004, it had 59 parishes and 132,779 Catholics with 137 priests.
At the time of the diocese's establishment in 1958, there were only 15 parishes with 18,000 Catholics. In 1970 when Bishop Nicholas Cheong Jin-suk, the first local bishop of Cheongju, was ordained, the diocese witnessed many developments.
What have made the diocese famous are its social welfare service and related institutions. Among them is Kottongne, the largest social welfare institute in the country. The Kottongne facility in Eumseong is home to about 3,000 handicapped people and homeless elderly people since it opened in 1976. Cheongju diocese has two martyrs' shrines. Among them is Baithi Martyrs' Shrine which is well known to Korean faithful. During the persecutions of 1866 and 1868, 55 Catholics were martyred around the shrine. The other is Yeonpung Martyrs' Shrine.
Cheongju diocese has been focusing on education, as well as social welfare. Schools include Maegoe middle and high school, Yangeob high school and Kottongne Hyundo University of Social Welfare.
In Cheongju diocesan jurisdiction, the population is 1,417,053 at the end of 2016. (Some 2.7 percent of the whole population of 51 million in the country). Most residents are ethnic Koreans.
Standard Korean is in use. English, a mandatory subject in schools, can be spoken and understood in business and tourist areas. All the traffic signs are explained in English as well as Korean.
Cheongju diocese falls within the temperate zone and has the four distinctive seasons of spring, summer, autumn and winter. The yearly average temperature is 11.6 degrees Celsius. The annual precipitation in the region averages 1,216 millimeters. Most of the rainfall is concentrated in the rainy months (monsoon period) of June through September.
The Chungcheongbuk-do province is located in the center of the Korean peninsula and the average altitude of the region is some 180 meters. Cheongju city, with its many universities, is known to people as the "city of education."