List of bishops of Sion explained

Late Antiquity

width=110px	From	width=110px	To	Bishop	Notes
585		Heliodorus
613	614	Leudemond
647	653	Prothais
673	690	Saint Aimé
762	765	Willicar
786/8	796/8	Altheus
fl. 805		Theodore III(?)	According to 12th-century legend, secular power was granted to the bishops of Sion by Charlemagne
fl. 824		Adalongus
825	857	Heyminus
877	899/900	Waltherius
932		Asmundus
fl. 940		Manfredus (?)
983	984/5	Amizo

width=110px	From	width=110px	To	Bishop	Notes
993/4	1018/20	Hugues	First prince-bishop, granted secular power by Rudolph III of Burgundy in c. 999
1034	1053/4	Aymon of Savoy	Succeeded his brother Buchardus as Abbot of St Maurice in 1049 or 1050
1054	1087-1090	Ermenfroi
fl. 1092		Gausbertus
1107	1116	Vilencus
1135	1138	Boson
1138	1150	Saint Guérin
1150	1162(?)	Louis
1162	1168 (?)	Amédée of La Tour
1176	1177	Guillaume of Blonay
1179	1181 or 1184	Conon
1184(?)	1196	Guillaume of Candie
1196	1203	Nantelme of Écublens
1203	1205	Guillaume of Saillon
1206	1237	Landry of Mont
1237	1243	Boson II of Granges
1243	1271	Henri of Rarogne
1271	1273	Rodolphe of Valpelline
1273	1287	Pierre of Oron
February 1287	15 December 1289		vacant
1289	1308	Boniface of Challant
1308	1323	Aymon of Châtillon
1323	1338	Aymon of La Tour
1338	1342	Philippe of Chamberlhac
1342	1375	Guichard Tavelli	Murdered by defenestration
1375	1386	Édouard of Savoy

width=110px	From	width=110px	To	Bishop	Notes
1386	1386	Guillaume of La Baume-Saint-Amourb
1387	1387	Robert Chambrier
1388	1392	Humbert de Billens
1398	1404	Aymon Séchala
1404	1417	Jacques (Antoine?) de Challant

width=110px	From	width=110px	To	Bishop	Notes
1387	1388	Gerardus (Girard Tavel?)
1392	1393	Henri de Blanchis
1394	1402	Guillaume IV ("the Good") of Rarogne
1402	1418	Guillaume V of Rarogne	see Raron affair

width=110px	From	width=110px	To	Bishop	Notes
1418	1437	André dei Benzi of Gualdo	Archbishop of Kolocza (in Hungary); administrator from 1418, bishop from 1431. Valais witch trials.
1437	1451	Guillaume VI of Rarogne
1451	1457	Henri Asperlin
1457	1482		Burgundian War
1482	1496	Jost of Silenen (d. 1498)	Member of Lucerne nobility (uncle of Kaspar von Silenen) and diplomat for the Swiss Confederacy, bishop of Grenoble 1477 - 1467, Jost ruled as a "Renaissance prince" but after failed campaigns against Milan was forced to abdicate and went into exile in Lyon, retaining only the title of titular bishop of Hierapolis.
1496	1499	Nicolas Schiner
1499	1522	Mathieu Schiner	Cardinal; nephew of Nicolas Schiner
1522	1528	Philippe am Hengart (not recognised by the Pope) Philippe de Platea (not recognised locally)
1529	1545	Adrien I of Riedmatten	Valais becomes an eternal associate of the Old Swiss Confederacy in 1529.
1548	1565	Jean Jordan
1565	1604	Hildebrand I of Riedmatten	Banned protestantism in 1604^[1]
1604	1613	Adrien II of Riedmatten
1613	1638	Hildebrand II Jost	In 1628, the Valais becomes a republic, but remains under the nominal rule of the prince-bishops.
1638	1640
1640	1646	Adrien III of Riedmatten
1646	1672	Adrien IV of Riedmatten
1672	1701	Adrien V of Riedmatten
1701	1734
1734	1752	Jean-Joseph-Arnold Blatter
1752	1760	Jean-Hildebrand Roten
1760	1780	François-Joseph-Frédéric Ambuel
1780	1790	François-Melchior-Joseph Zen-Ruffinen
1790	1807		Last prince-bishop, loss of secular power with the French invasion of 1798.

width=110px	From	width=110px	To	Bishop	Notes
1807	1817	Joseph-François-Xavier de Preux
1817	1829	Auguste-Sulpice Zen-Ruffinen
1830	1843	Maurice-Fabien Roten
1843	1875	Pierre-Joseph de Preux
1875	1901	Adrien VI Jardinier
1901	11 July 1918	Jules-Maurice Abbet	Born 11 September 1845
1919	19 March 1952	Victor Bieler	Born 16 March 1881
1952	1975	François-Nestor Adam	Born 7 February 1903; died 8 February 1990
1975	1995	Henri Schwery	Born 14 June 1932
1995	2014	Norbert Brunner	Born 21 June 1942
2014		Jean-Marie Lovey	Born 2 August 1950

Encyclopedia: Historical Dictionary of Switzerland. Zenhäusern, Gregor. Sion (diocèse). fr. 12 February 2021. Laurent Auberson.