Discover the Diocese of Rockville Center

The Roman Catholic Diocese of Rockville Centre (LatinDioecesis Petropolitana in Insula Longa) comprises the territory of Nassau and Suffolk counties (regionally known as Long Island) in New York state, USA. Founded in 1957, this diocese was created from territory that once belonged to the Diocese of Brooklyn. It is the sixth-largest Catholic diocese in the United States, currently serving approximately 1.5 million people in 134 parishes. The Most Reverend William Murphy has served as the diocese's fourth bishop since 2001. Murphy arrived in Long Island from his native Archdiocese of Boston, where he served as the archdiocese's vicar general. The diocese is named for the village where its cathedralSt. Agnes Cathedral, is located, Rockville Centre in Nassau County.


Most Reverend Walter P. Kellenberg served as first bishop of the diocese from 1957-1976. Kellenberg was followed by Bishop John McGann, who retired in 2000 and died in 2002. The diocese was led briefly by Bishop James T. McHugh, who died of cancer on December 10, 2000.



The following is a list of the diocesan bishops of the Diocese of Rockville Centre (and their terms of service):

  1. Bishop Walter P. Kellenberg (1957–1976) †
  2. Bishop John R. McGann (1976–2000) †
  3. Bishop James T. McHugh (2000) †
  4. Bishop William F. Murphy (2001–present)

† = deceased




† = deceased


Seminary of the Immaculate Conception

High schools



Elementary schools



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