YIHSIEN, APOSTOLIC PREFECTURE OF. — In the north-western part of the province of Hopeh (northern China).
It was erected as a mission *sui iuris* on 25 May 1929, comprising three civil subprefectures Paoting (v.) and one district (Sanpuò) of that of Peking (v.), and was entrusted to the Congregation of the Priests of the Sacred Stigmata of Our Lord Jesus Christ, whose religious had been present in the area since 1927. On 9 December 1935 it was elevated to an apostolic prefecture.
It covers an area of approximately 7,900 km². As of 30 June 1947, with a total population of approximately 500,000, there were 6,300 Catholics; 16 priests, of whom 6 were Chinese; 2 major seminarians and 18 minor seminarians; 1 lay brother; and 39 sisters, only 3 of whom were foreigners. Among its works were 1 hospital, 2 orphanages, 3 dispensaries, and 14 schools.
The evangelization of the territory of Y. began in the early decades of the last century through the missionaries of Peking; the field remained particularly difficult even a century later. Of the 2,472 Christians handed over to the Stigmatines in 1927, the descendants of the first converts formed a notable nucleus of approximately 500 faithful in the subprefecture of Kwangchang and a smaller one of about 150 in that of Laishui; the rest were all neophytes, distributed across 18 small centres.