Parnassus is a former Roman town and bishopric in Asia Minor (Asian modern Turkey) and present Latin Catholic titular see.
As a town in the Late Roman province of Cappadocia Tertia, Parnassus was important enough to become a suffragan bishopric of the Metropolitan of Mocissus, but it faded. Its site is near modern Parlasan.
The diocese was nominally restored as a titular bishopric in 1895.
It is vacant, having had the following incumbents, all of the lowest (episcopal) rank :
Johann Baptist Schneider (1896.06.25 – death 1905.01.26) as Auxiliary Bishop of Wien (Vienna, Austria) (1896.06.25 – 1905.01.26)
Ludovic Joseph Legraive (1907.10.17 – death 1940.06.10) as Auxiliary Bishop of Mechelen (Mechlin, Belgium) (1907.10.17 – 1940.06.10)
Arturo Mery Beckdorf (1941.03.22 – 1944.07.29), later Titular Archbishop of Phasis (1955.04.20 – 1976.05.28)
Daniel Figueroa Villón (1945.04.12 – 1946.09.22) as Auxiliary Bishop of Antofagasta (Chile) (1941.03.22 – 1944.07.29); later Coadjutor Bishop of Valdivia (Chile) (1944.07.29 – 1955.04.20), Coadjutor Archbishop of Santiago (Chile) (1955.04.20 – 1961.05.14), Titular Archbishop of Phasis (1955.04.20 – 1976.05.28) as Auxiliary Bishop of La Serena (Chile) (1961.05.14 – 1963) promoted Coadjutor Archbishop of La Serena (Chile) (1963 – death 1976.05.28)
Daniel Tavares Baeta Neves (1947.03.29 – 1958.05.16) as Auxiliary Bishop of Mariana (Brazil) (1947.03.29 – 1958.05.16); later Bishop of Januária (Brazil) (1958.05.16 – 1962.06.01), Titular Bishop of Alexandria Minor (1962.06.01 – 1964.06.04), Bishop of Sete Lagoas (Brazil) (1964.06.04 – death 1980.07.08)
Adolfo Luís Bossi, Capuchin Friars (O.F.M. Cap.) (1958.06.18 – 2002.05.08) as Coadjutor Bishop-Prelate of São José do Grajaú (Brazil) (1958.06.18 – 1966.02.19), succeeding as Bishop-Prelate of São José do Grajaú (1966.02.19 – retired 1970.08.22), died 2002.
