Roman Catholic Diocese of Santa Rosa in Argentina Tags: Clerical Administrative Region, Diocese.The Roman Catholic Diocese of Santa Rosa in Argentina is located in the city of Santa Rosa La Pampa Argentina. It was established by Pope Pius XII on 11 February 1957 and is a suffragan diocese in the province of Bahía Blanca. thumbnail area (km2) 1.4344e+11 country Argentina Established 11 February 1957 ( years ago) province Roman Catholic Archdiocese of Bahía Blanca Learn more... Loading...