The Diocese of Helena was established on March 7, 1884, and initially included the entire state of Montana. Its present boundaries were established on May 18, 1904, when the Diocese of Great Falls (now Great Falls-Billings) was formed from its territory. The diocese covers 51,922 square miles of western and north central Montana, encompassing 21 counties and parts of two others. The diocese’s 58 parishes and 38 missions are structured into six deaneries: Bozeman, Butte, Conrad, Helena, Kalispell, and Missoula. Its diocesan church is the Cathedral of St. Helena, which was dedicated in 1914 and is located in Helena.

Former Bishops

The nine bishops to serve the Helena Diocese prior to Bishop Thomas are:


The Diocese At A Glance
  • 51,922 square miles
  • 57 parishes, 38 missions
  • 17,241 registered households
  • 44,413 Catholics registered in the parishes
  • 79 priests:
    • 72 diocesan priests:
    • 45 priests assigned in the diocese (2 on leave)
    • 26 priests on senior status (5 have assignments)
    • 5 priests serving outside the diocese
    • 9 priests from other dioceses serving/living here
    • 5 Jesuit priests and 1 Missionary Priest of Africa serving in the diocese
  • 15 men preparing for priestly ordination (seminarians)
  • 42 permanent deacons
  • 32 religious sisters serving in the diocese
  • 2 religious brothers serving in the diocese
  • 1,130 children enrolled in diocesan schools
  • 3,498 children and youth enrolled in religious education