HAIMEN, DIOCESE OF. — It is located in central-eastern China, north of the Yangtze River. It was erected as an apostolic vicariate on 11 August 1926, with territory detached from the mission of Nanjing, which at that time included the entire civil province of Jiangsu, and was entrusted to the Chinese secular clergy. On 11 April 1946, with the establishment of the episcopal hierarchy in China, it was elevated to a suffragan diocese of Nanjing.
It covers an area of 13,500 sq km. As of 30 June 1947, with a population of approximately 5,000,000 inhabitants, there were 39,744 Catholics and 175 catechumens. In addition to the bishop, there were 43 Chinese priests and 3 foreign priests. The auxiliary personnel consisted of 50 native sisters and 9 foreign sisters, plus an unspecified number of catechists, teachers, and baptizers, a number that had been quite large in previous years. The minor seminary had 13 students, and the preparatory seminary also had 13. At the regional seminary of Jiangsu in Zikawei, near Shanghai, the diocese of H. had 11 seminarians: 4 in philosophy and 7 in theology. Among the institutions, reduced and hindered by the war, there were 4 middle schools with 493 pupils, 52 primary schools with 2,787 pupils, and 75 prayer and elementary schools with 1,247 attendees. There were also 2 orphanages with 41 residents and 38 medical dispensaries, which during the 1946–47 period had provided 35,875 consultations.
The Christian beginnings in this mission date back to the 17th century, when in 1638 the Jesuit Fr. Brancati arrived on the island of Chongming, at the mouth of the Yangtze River, and found as collaborators in his apostolate the Chinese physician Siu Ki-yeuen and the benefactress Candida Hiu, also Chinese.