List of states in the Holy Roman Empire (O)

This is a list of states in the Holy Roman Empire beginning with the letter O. Some historians mark the beginning of the Empire as 800, with the coronation of Frankish king Charlemagne ("Charles the Great").

Name Type Imperial circle Imperial diet History
Oberbronn Lordship n/a n/a 1232: First mentioned; fief of Lichtenberg
1352: Sold to Ochsenstein as fief of Lichtenberg
1382: Sold to Lichtenberg
1456: Sold to Lützelstein as fief of Lichtenberg
1480: To Zweibrücken-Bitsch
1551: To Leiningen-Westerburg-Leiningen
1622: To Leiningen-Westerburg-Oberbronn[citation needed]
1665: 2/3 to Hesse-Homburg, 1/3 to Sinclair[citation needed]
1727: Hessian portion to Hohenlohe-Waldenburg-Bartenstein
1732: Sinclair portion to Lewenhaupt
1764: Part of Hohenlohe portion to de Dietrich
1789: All to France
Oberehnheim (Obernai) Imperial City Upp Rhen RH 1240: Free from monastic control as town
1354: Joins Décapole
1679: To France
Oberelsaß
See: Upper Alsace		 Landgraviate
Obermünster in Regensburg Abbacy Bav RP 800s: Established with imperial immediacy
1315: HRE Princess of the Empire
1802: To the Archbishopric of Regensburg
1810: To Bavaria; suppressed
Oberried Provostry n/a n/a 1237: Formed
1249: Abolished[citation needed]
1255: Reestablished[citation needed]
1496: Advocacy to Freiburg within Further Austria
1725: Advocacy to St Blaise's Abbey within Further Austria[citation needed]
1806: To Baden
Obersalm
See: Salm in the Vosges		 County
Oberstein Lordship n/a n/a 1075: First mentioned; to Stein
1250: Line Daun-Oberstein established
1364: Partitioned into Oberstein-Gundheim and Oberstein-Kredenburg[citation needed]
Oberstein-Gundheim Lordship n/a n/a 1364: Partitioned from Oberstein[citation needed]
1661: Extinct; to the Palatinate
1699: To Greiffenclau
Oberstein-Kredenburg Lordship n/a n/a 1364: Partitioned from Oberstein[citation needed]
1602: to Schmidtburg
1611: Extinct; to Speyer
Obwalden Imperial Valley n/a n/a 11th Century:To Lenzburg
12th Century: Donated to Beromünster Abbey
?: To Murbach Abbey[citation needed]
1291: Sold to Habsburg; with Nidwalden became a founding member of the Swiss League.
1309: Imperial immediacy
1648: Left Empire as member of Swiss Confederation
Ochsenhausen 1391: Abbey Swab SP 1093: Priory of St. Blaise's Abbey
1391: Independent abbey
1495: Imperial immediacy
1803: To Schaesberg-Retersbeck (Tannheim), Sinzendorf (Winterrieden) and Metternich-Winneburg and Beilstein (remainder)
1806: All to Württemberg
Ochsenstein Lordship n/a n/a 1187: First mentioned; branch of Geroldseck
1391: Quarter of Ochsenstein sold to the Palatinate
1485: Extinct; to Zweibrücken-Bitsch
Odenheim and Bruchsal Abbey
1503: Provostry		 Upp Rhen RP 1100–18: Established
1494: Secularization
1507: Relocated to Bruchsal
1803: To Baden
Oettingen (Öttingen) County n/a n/a 1141: First mentioned
1363: Acquired Spiegelberg[citation needed]
1410: Partitioned into Oettingen-Oettingen and Oettingen-Wallerstein
Oettingen-Baldern County Swab SC 1623: Partitioned from Oettingen-Wallerstein
1798: Extinct; to Oettingen-Wallerstein
Oettingen-Flochberg County Swab SC 1442: Partitioned from Oettingen-Wallerstein
1522: Partitioned into itself and Oettingen-Wallerstein[citation needed]
1548: Extinct; to Oettingen-Wallerstein[citation needed]
Oettingen-Oettingen County
1674: Principality		 Swab SC 1410: Partitioned from Oettingen
1440: Extinct; to Oettingen-Wallerstein[citation needed]
1442: Partitioned from Oettingen-Wallerstein
1674: HRE Prince
1731: Extinct; to Oettingen-Wallerstein
Oettingen-Spielberg County
1734: Principality		 Swab SC / PR 1623: Partitioned from Oettingen-Wallerstein
1734: HRE Prince
1803: Bench of Princes
1806: To Bavaria
1810: Parts to Württemberg
Oettingen-Wallerstein County
1774: Principality		 Swab SC / PR 1410: Partitioned from Oettingen
1442: Partitioned into Oettingen-Oettingen, itself and Oettingen-Flochberg
1486: Extinct; divided between Oettingen-Flochberg and Oettingen-Oettingen[citation needed]
1522: Partitioned from Oettingen-Flochberg[citation needed]
1549: Extinct; to Frederick V of Oettingen-Oettingen by marriage, who assumed the name Oettingen-Wallerstein[citation needed]
1623: Partitioned into Oettingen-Spielberg, itself and Oettingen-Baldern
1774: HRE Prince
1803: Bench of Princes
1806: To Bavaria
1810: Parts to Württemberg
Offenburg Imperial City Swab SW 1148: First mentioned
1240: Imperial Free City
1803: To Baden
Olbrück Lordship Low Rhen WE 1190: Comissioned by Wied to the Archbishopric of Cologne
1244: Wied extinct; Olbrück was divided and shared ultimately with a dozen families, often in dispute with each other[citation needed]
1555: All to Waldbott von Bassenheim
1794: To France
1815: To Prussia[citation needed]
Oldenburg
Grand Duke of Oldenburg, Heir in Norway, Duke of Schleswig, Holstein, Stormarn, Ditmarshes & Oldenburg, Prince of Lübeck and Birkenfeld, Lord of Jever and Kniphausen		 County
1777: Duchy
1815: Grand Duchy		 Low Rhen PR 1108: First mentioned; fief of Saxony
1143: Partitioned into Wildeshausen and itself[citation needed]
1180: Imperial immediacy
1262: Partitioned into itself and Oldenburg-Delmenhorst
1447: Reunited with Oldenburg-Delmenhorst
1463: Partitioned into itself and Oldenburg-Delmenhorst
1547: Reunited with Oldenburg-Delmenhorst
1577: Partitioned into itself and Oldenburg-Delmenhorst
1617: Reunited with Oldenburg-Delmenhorst
1667: Extinct; to Denmark
1773: To Paul of Russia; then to Frederick Augustus of Lübeck
1777: HRE Duke
1810: To France
1815: Restored, Grand Duke
Oldenburg-Delmenhorst County Low Rhen PR 1262: Partitioned from Oldenburg
1447: Extinct; to Oldenburg
1463: Partitioned from Oldenburg
1482: To Oldenburg[citation needed]
1483: To the Bishopric of Münster[citation needed]
1484: Extinct[citation needed]
1547: To Oldenburg
1577: Partitioned from Oldenburg
1617: Extinct; to Oldenburg
Orange County
1173: Principality		 none none 11th century: Independence from Provence
1121: Extinct in male line; to Aumelas by marriage
1173: Extinct; to Baux by marriage; HRE Prince
1193: To Baux-Orange
1289: Acquired Baux
1417: Extinct; to Chalon-Arlay
1544: To William of Nassau-Dillenburg, who took the name Orange-Nassau
1702: To France, who enfeoffed Francis Louis of Conti
1713: To France, attached to the Dauphiné
Orange-Nassau Principality none none 1544: Created when William of Nassau-Dillenburg inherited Orange
1702: Extinct; succession dispute between Nassau-Dietz who took the name Orange-Nassau, and Prussia. Orange itself seized by France
1739: Acquired Nassau-Hadamar and Nassau-Dillenburg
1743: Acquired Nassau-Siegen
1747: Acquired the Netherlands
1795: Left bank territory to France
1806: United with Nassau-Orange-Fulda; then dispersed between various states
1815: King of the Netherlands and Grand Duke of Luxembourg
Orlamünde County n/a n/a 1032-1040: Mentioned, to counts of Orlamünde
By 1060: Extinct; to Weimar
1062: To Weimar-Orlamünde
Orsini and Rosenberg
Prince of Orsini and Rosenberg, Baron of Lerchenau and Grafenstein		 1681: HRE Count (Personalist)
1790: HRE Prince (Personalist)		 n/a FR 1681: Formed
13th century: First mentioned
1681: Granted personalist vote in the Bench of Franconian Counts
1684: Adopted style of Orsini-Rosenberg
Ortenau (Mortenau) Landvogtei n/a n/a 763: First mentioned; gau county of the Carolingian Empire
1007: To the Bishopric of Bamberg
?: To Zähringen
1218: Seized by the Emperor
1261: To Geroldseck
The Ortenau disintegrated soon after, though the title was held variously by Bach, Fürstenberg, Mörsperg, Ochsenstein and Oettingen, amongst others
1803: Much of the Ortenau to Breisgau-Modena and Baden
1819: All to Baden
Ortenburg in Carinthia County n/a n/a 1072: First mentioned; possibly related to Grögling-Hirschberg
1306: Imperial immediacy
1418: Extinct; to Celje
1456: Extinct; to Austria
Ortenburg (Ortenberg)
Count of Ortenburg, Count and Lord of Tambach		 County Bav WT 1135: Partitioned from Carinthia in the former lands of Vohburg-Passau
1145: Acquired advocacies around Passau
1158: Acquired much of Vornbach
1163: Acquired Murach
1173: Acquired Kraiburg and Marquartstein
1188: Acquired Sulzbach; partitioned into Ortenburg-Kraiburg and Ortenburg-Ortenburg
1272: Remaining territories held by Ortenburg-Ortenburg; henceforth known as Ortenburg
1319: Acquired Wildenegg
1381: Side line Ortenburg-Dorfbach founded
1395: Partitioned into Ortenburg-Neuortenburg and Ortenburg-Altortenburg
1446: Reunited by Ortenburg-Neuortenburg
1517: Acquired Mattighofen
1805: To Bavaria; received in exchange Tambach
1806: Tambach to Bavaria
Ortenburg-Altortenburg County n/a n/a 1395: Partitioned from Ortenburg
1416: Acquired Niederaltaich Abbey
1446: Extinct; to Ortenburg-Neuortenburg
Ortenburg-Dorfbach County n/a n/a 1381: Founded upon marriage of Alrams I with Barbara von Rottau; fief of Ortenburg
1431: Imperial immediacy
1461: Extinct; to Ortenburg-Neuortenburg
1652: Sold to Peckenzell
Ortenburg-Kraiburg County n/a n/a 1188: Partitioned from Ortenburg
1200: Acquired Rotter
1208: Acquired County Palatine of Bavaria and Neuburg
1217: Acquired Griesbach-Waxenberg
1239: Lost Ramsau and territories in Brixen to Regensburg
1248: Extinct in male line; lost County Palatine of Bavaria
1256: To Werdenberg-Sargans by marriage
1259: Sold to Lower Bavaria
Ortenburg-Murach County n/a n/a 1238: Partitioned from Ortenburg-Ortenburg
1268: Made fief of Upper Bavaria
1272: Sold to Upper Bavaria
1285: Extinct
Ortenburg-Neuortenburg County n/a n/a 1395: Partitioned from Ortenburg
1445: Acquired Saldenburg
1446: Renamed to Ortenburg
Ortenburg-Ortenburg County n/a n/a 1188: Partitioned from Ortenburg
1217: Acquired Neustadt
1229: Imperial immediacy
1238: Partitioned into itself and Ortenburg-Murach
1257: Extinct; to Gebhard of Ortenburg-Murach
1272: Renamed to Ortenburg
Osnabrück Bishopric Low Rhen EC 783: Fief of Saxony
1180: Fief of Tecklenburg
1226: HRE Prince of the Empire
1236: Imperial immediacy
After 1648: Osnabrück alternately ruled by a Protestant Administrator and Catholic Prince-Bishop
1803: To Hanover
1806: To Prussia
1807: To Westphalia
1810: To France
1815: To Hanover
Osterberg Lordship
1712: Barony		 n/a n/a 1225: First mentioned; to Elchingen Abbey
by 1448: Sold to Ochsenhausen Abbey
1455: Sold to Rechberg-Hohenrechberg
1460: To Rechberg-Kronburg
1577: To Rechberg-Osterberg
1679: Sold to Meyer von Röfingen auf Bühl who assumed the name Osterberg
1712: HRE Barony
1806: To Bavaria
Öttingen
See: Oettingen
Ottobeuren Abbacy Swab SP 764: Formed
1299: Imperial immediacy
1624: Fief of the Bishopric of Augsburg
1710: Imperial immediacy
1802: To Bavaria
Overijssel Lordship Burg n/a 11th Century: Territory nominally ceded to the Bishopric of Utrecht as the Oversticht
1336: To Guelders
1347: To the Bishopric of Utrecht
1528: To the Spanish Netherlands; Burgundian Circle
1580: To the Netherlands
1795: To the Batavian Republic
1810: To France
1815: To the Netherlands

References

  1. ↑ "Charlemagne | Holy Roman emperor". Encyclopædia Britannica Online. Retrieved 16 October 2023.
  2. 1 2 3 4 5 6 7 8 9 "Geschichte von Oberbronn" (in German). oberbronn.de. Retrieved 27 August 2026.
  3. ↑ Wirth, Markus (2009). Hohenloher Herrschaft im Elsass: Handlungsspielräume eines mindermächtigen Reichsstandes in geographisch entlegenen Besitzungen am Beispiel der Seigneurie Oberbronn, 1727-1789/93 (in German). pp. 32–35.
  4. 1 2 "Obernai: A little history..." tourisme-obernai.fr. Retrieved 28 August 2026.
  5. ↑ "Découvrez l'Histoire d'Obernai à travers son patrimoine" (in French). obernai.fr. Retrieved 28 August 2026.
  6. 1 2 3 Morbach, Peter. "Regensburg, Obermünster" (in German). hdbg.eu. Archived from the original on 7 March 2016.
  7. ↑ Klimstein, Franz (2010). "Die Säkularisation von 1802/1803 auf dem Gebiet der Diözese Regensburg 2. Teil: Säkularisierte und nicht aufgelöste Klöster, Stifte und Kommenden" (PDF). Mitterfelser Magazin (in German).
  8. ↑ "Oberried Municipality (Germany)". crwflags.co. Retrieved 27 August 2026.
  9. 1 2 "Oberried in Vergangenheit und Gegenwart" (in German). oberried.de. Retrieved 27 August 2026.
  10. ↑ Steinbach, Martin. "Os museus no paraíso das joias alemãs" (in Portuguese). incolormagazine.com. Retrieved 31 August 2026.
  11. ↑ "Schloss Oberstein". great-castles.com. Retrieved 31 August 2026.
  12. 1 2 "Gundheimer Geschichte" (in German). heimatverein-gundheim.de. Retrieved 1 September 2026.
  13. 1 2 "Schloss Kredenburg" (in German). alleburgen.de. Retrieved 1 September 2026.
  14. 1 2 3 Garovi, Angelo. "Obwalden" (in German). Historisches Lexikon der Schweiz. Retrieved 2 September 2026.
  15. ↑ Coolidge, Rev. William Augustus Brevoort (1911). "Unterwalden" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 27 (11th ed.). Cambridge University Press. pp. 780–81.
  16. ↑ "Switzerland (05/99)". 2009-2017.state.gov. Retrieved 2 September 2026.
  17. 1 2 "Geschichte der Klosteranlage" (in German). landesakademie-ochsenhausen.de. Retrieved 3 September 2026.
  18. ↑ "Über die Stadt". ochsenhausen.de. Retrieved 3 September 2026.
  19. ↑ "Zeitgeschichte von Winterrieden" (in German). winterrieden.de. Retrieved 3 September 2026.
  20. ↑ "Ortsgeschichte" (in German). gemeinde-tannheim.de. Retrieved 3 September 2026.
  21. ↑ "Ochsenhausen - Altgemeinde~Teilort" (in German). leo-bw.de. Retrieved 3 September 2026.
  22. 1 2 3 "Ochsenstein" (in French). chateaux.greentortoise.fr. Retrieved 5 September 2026.
  23. 1 2 Nagel, Dennis; Braun, Karl-Heinz. "Kollegiatstift Odenheim - Geschichte" (in German). kloester-bw.de. Retrieved 5 September 2026.
  24. 1 2 "Odenheimer Hof - weitere Infos" (in German). hier-in-leingarten.de. Retrieved 5 September 2026.
  25. 1 2 3 4 5 6 7 "Geschichte Oettingen-Spielberg". Website des fürstlichen Hauses Oettingen-Spielberg (in German). Retrieved 2021-02-03.
  26. 1 2 3 4 5 6 7 8 9 10 11 12 Kudorfer, Dieter. "Oettingen, Grafschaft/Fürstentum" (in German). historisches-lexikon-bayerns.de. Retrieved 2026-09-06.
  27. ↑ Volckamer, Volker. "Oettingen" (in German). deutsche-biographie.de. Retrieved 2026-09-06.
  28. ↑ Constantin von Wurzbach: "Oettingen-Wallerstein, die Fürsten von, Genealogie." In: Biographisches Lexikon des Kaiserthums Oesterreich (Biographical Lexicon of the Empire of Austria).  Part 21 Kaiserlich-königliche Hof- und Staatsdruckerei, Vienna 1870, p. 29 (digitalised).
  29. 1 2 "Offenburg - history I". offenburg.de. Retrieved 2026-09-07.
  30. ↑ "Offenburg - history II". offenburg.de. Retrieved 2026-09-07.
  31. 1 2 3 "Burgruine Olbrück bei Niederdürenbach" (in German). kuladig.de. Retrieved 2026-09-08.
  32. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Wikisource This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Oldenburg (grand-duchy)". Encyclopædia Britannica. Vol. 20 (11th ed.). Cambridge University Press. pp. 71–72.
  33. ↑ "A Guide to the United States' History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: Oldenburg". history.state.gov. Retrieved 2026-09-10.