This is a list of states in the Holy Roman Empire beginning with the letter M. 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 Magdeburg Archbishopric Low Sax seeDuchy 968: Formed1180: Imperial immediacy1680: Secularised as Duchy for Brandenburg Magdeburg Burgraviate n/a n/a 1000: Enfieffed to Walbeck1080: Enfeoffed to Herman of Spanheim1118: To Groitzsch1136: Enfeoffed to Querfurt1178: To Querfurt-Magdeburg1269: To Saxe-Wittenberg Magdeburg Duchy Low Sax PR 1680: Archbishopric of Magdeburg secularised as Duchy for Brandenburg1807: Dissolved; west to Westphalia, east to Prussia Maidburg-Hardegg Burgraviate n/a n/a 1278: Younger branch of Querfurt-Magdeburg assumed the name Maidburg-Hardegg after inheriting Hardegg1481: To Austria1484: Extinct Mainau Commandry of the Teutonic Order Swab n/a 724: To Reichenau Abbey1271: To the Teutonic Order1730: Acquired Dettingen, Dingelsdorf and Litzelstetten1783: Acquired Allmannsdorf1806: To Baden Mainz Archbishopric1356: HRE Prince-Elector El Rhin EL 4th Century: Formed780: Archbishopric1356: HRE Prince-Elector1803: To the Archbishopric of Regensburg Mainz Imperial City n/a n/a 1244: Free Imperial City1462: To the Archbishopric of Mainz Malberg Lordship n/a n/a 1273: Acquired by Reifferscheid; to the Elder Line1302: To Luxembourg Manderscheid Lordship1457: County n/a n/a 1133: First mentioned1445: Acquired Schleiden1457: HRE Count1469: Acquired Blankenheim1488: Partitioned into Manderscheid-Schleiden, Manderscheid-Blankenheim-Gerolstein and Manderscheid-Kail Manderscheid-Blankenheim County Low Rhen WE 1530: Partitioned from Manderscheid-Blankenheim-Gerolstein1780: Extinct in male line; to Sternberg-Manderscheid by marriage Manderscheid-Blankenheim-Gerolstein County Low Rhen WE 1488: Partitioned from Manderscheid1530: Partitioned into Manderscheid-Gerolstein and Manderscheid-Blankenheim Manderscheid-Gerolstein County Low Rhen WE 1530: Partitioned from Manderscheid-Blankenheim-Gerolstein1697: Extinct; to Manderscheid-Blankenheim Manderscheid-Kail County Low Rhen WE 1488: Partitioned from Manderscheid1742: Extinct; to Manderscheid-Blankenheim Manderscheid-Schleiden County Low Rhen WE 1488: Partitioned from Manderscheid1545: Acquired Virneburg1560: Partitioned into Manderscheid-Schleiden-Kerpen and Manderscheid-Schleiden-Virneburg Manderscheid-Schleiden-Kerpen County Low Rhen WE 1560: Partitioned from Manderscheid-Schleiden1583: Under Imperial ban1593: Extinct; divided between Manderscheid-Kail and Mark-Schleiden in succession dispute Manderscheid-Schleiden-Virneburg County Low Rhen WE 1560: Partitioned from Manderscheid-Schleiden1590: Extinct in male line; to Manderscheid-Gerolstein by marriage1639: To Löwenstein-Wertheim-Virneburg by marriage Mansfeld County n/a n/a 1050: First mentioned as a title of the gau counts in Hassegau1112: Count of Mansfeld primary title 1215: Partitioned into itself and Friedeberg1229: Extinct; to Querfurt-Mansfeld1246: Querfurt-Mansfeld assumed the name Mansfeld1266: Partitioned into itself and Schraplau1273: Partitioned into Mansfeld Elder Line and Mansfeld Younger Line Mansfeld-Arnstein County Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1580: Mediatised; 3/5 to Saxony, 2/5 to Magdeburg1615: Extinct; divided between Mansfeld-Artern, Mansfeld-Bornstedt, Mansfeld-Eisleben and Mansfeld-Friedeburg Mansfeld-Artern County Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1580: Mediatised; 3/5 to Saxony, 2/5 to Magdeburg1631: Extinct; divided between Mansfeld-Bornstedt and Mansfeld-Eisleben Mansfeld-Bornstedt HRE Prince and Prince of Fondi, Count and Lord of Mansfeld, Noble Lord of Heldrungen, Seeburg and Schraplau, Lord of the Lordship of Dobrzisch, Neuhaus and Arnstein County Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1580: Mediatised; 3/5 to Saxony, 2/5 to Magdeburg1780: Extinct; Saxon portion to Saxony, Magdeburgian portion to Magdeburg. Mansfeld property in the Habsburg domain to Austria1789: Austrian fiefs to Colloredo-Mansfeld Mansfeld-Eisleben County Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1580: Mediatised; 3/5 to Saxony, 2/5 to Magdeburg1710: Extinct; to Mansfeld-Bornstedt Mansfeld Elder Line County n/a n/a 1273: Partitioned from Mansfeld1313: Extinct; to Mansfeld Younger Line Mansfeld-Friedeburg County1594: Principality Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1580: Mediatised; 3/5 to Saxony, 2/5 to Magdeburg1594: HRE Prince1626: Extinct; divided between Mansfeld-Artern, Mansfeld-Bornstedt and Mansfeld-Eisleben Mansfeld-Heldrungen County Upp Sax WT 1563: Partitioned from Mansfeld-Vorderort1572: Extinct; divided between Mansfeld-Arnstein, Mansfeld-Artern, Mansfeld-Bornstedt, Mansfeld-Eisleben and Mansfeld-Friedeburg Mansfeld-Hinterort County Upp Sax WT 1501: Partitioned from Mansfeld Line 11547: Under Imperial Ban1552: Imperial Ban lifted1560: Partitioned into Mansfeld-Hinterort Elder Line, Mansfeld-Hinterort Intermediate Line and Mansfeld-Hinterort Younger Line Mansfeld-Hinterort Elder Line County Upp Sax WT 1560: Partitioned from Mansfeld-Hinterort1666: Extinct; divided between Mansfeld-Bornstedt and Mansfeld-Eisleben Mansfeld-Hinterort Intermediate Line County Upp Sax WT 1560: Partitioned from Mansfeld-Hinterort1628: Extinct; to Mansfeld-Hinterort Elder Line Mansfeld-Hinterort Younger Line County Upp Sax WT 1560: Partitioned from Mansfeld-Hinterort1594: Extinct; divided between Mansfeld-Hinterort Elder Line and Mansfeld-Hinterort Intermediate Line Mansfeld Line 1 County n/a n/a 1420: Partitioned from Mansfeld Younger Line1442: Acquired half of Friedeburg, and Salzmünde1482: Acquired Heldrungen1492: Extinct; to Mansfeld Line 2 Mansfeld Line 2 County n/a n/a 1420: Partitioned from Mansfeld Younger Line1449/52: Acquired Artern1501: Partitioned into Mansfeld-Vorderort, Mansfeld-Mittelort and Mansfeld-Hinterort Mansfeld Line 3 County n/a n/a 1420: Partitioned from Mansfeld Younger Line1442: Acquired half of Friedeburg1499: Extinct; to Mansfeld Line 2 Mansfeld-Mittelort (Mansfeld-Schraplau) County Upp Sax WT 1501: Partitioned from Mansfeld Line 11602: Extinct; to the lines of Mansfeld-Hinterort Mansfeld-Vorderort County Upp Sax WT 1501: Partitioned from Mansfeld Line 11563: Partitioned into Mansfeld-Bornstedt, Mansfeld-Eisleben, Mansfeld-Friedeburg, Mansfeld-Arnstein, Mansfeld-Artern and Mansfeld-Heldrungen1580: Mansfeld-Vorderort mediatised; 3/5 to Saxony, 2/5 to Magdeburg Mansfeld Younger Line County n/a n/a 1273: Partitioned from Mansfeld1420: Partitioned into Mansfeld Line 1, Mansfeld Line 2 and Mansfeld Line 3 Marchtal Abbacy Swab SP bef. 776: Formed1500: Imperial immediacy1803: To Thurn and Taxis1806: To Württemberg Mark (Marck) 1198: County Low Rhen PR 1226: Renamed from Altena-Berg1299: Acquired Arenberg1328: Partitioned into itself and Mark-Arenberg1391: To Cleves1394: To Cleves-Mark1521: To Jülich-Cleves-Berg1609: Extinct; War of Jülich Succession between Brandenburg and Palatinate-Neuburg1614: To Brandenburg1807: To France1808: To Berg1813: To Prussia Mark-Arenberg (Marck-Arenberg) County Low Rhen WE 1328: Partitioned from Mark1454: Partitioned into itself and Mark-Rochefort1547: To Ligne by marriage; who assumed the name Arenberg Mark-Rochefort (Marck-Rochefort) County n/a n/a 1454: Partitioned from Mark-Arenberg1544: Extinct; to Louis of Stolberg-Stolberg, founder of line Stolberg-Rochefort Mark-Schleiden (Marck-Schleiden) County Low Rhen WE 1593: Philip of Marck inherited part of Manderscheid-Schleiden-Kerpen, assumed the name Mark-Schleiden1774: Extinct; to Arenberg Marmoutier (Maursmünster) Abbacy Upp Rhen SP by 659: Formed659: Imperial immediacy1648: To France1789: Suppressed Martinstein Lordship n/a n/a Formerly to Daun1340: To the Archbishopric of Mainz1353: Enfeoffed to Grasewege1389: Enfeoffed to Merxheim 1555: Enfeoffed to Hunoltstein and Sickingen1655: Sovereignty to Schönborn1660: Enfeoffed to Weyers-Leyen and Ebersberg1716: Sovereignty to Baden1771: Ebersberg fief to Baden1795: To France1815: To Prussia Massa and Carrara (Malaspina) Marquisate1568: Principality1662: Duchy of Massa and Principality of Carrara n/a n/a 1473: Formed when Massa acquired Carrara1568: HRE Prince1664: HRE Duke1796: To the Cispadane Republic1797: To the Cisalpine Republic1802: To Italy1815: Restored1829: To Modena and Reggio Matsch Barony n/a n/a 12th Century: Formed1278: Acquired Tarasp1344: Acquired Castels1348: Lost Chiavenna, Puschlav and Bormio to Milan1365?: Acquired Greifenstein1372: Sold Malans to Underwegen1394: Lost Greifenstein to the Bishopric of Chur1400: Acquired Steinsberg1421: Lost Advocacy of Marienberg and Müstair to the Tyrol1464: Sold Tarasp to the Tyrol1487: Under Imperial Ban1496: Sold Castels to Austria1504: Extinct; remaining territories to Trapp Maulbronn Abbacy Swab SP 1147: Established with imperial immediacy1504: Made fief of Württemberg1534: Abbey suppressed1548: Abbey restored as fief of Württemberg1807: Secularised and suppressed Mechelen (Malines) Lordship1490: County (title remained "Lord") Burg n/a 910: Fief of Bishop of Liège1333: To Flanders1369: To Burgundy1483: To the Burgundian Netherlands1516: To the Spanish Netherlands1713: To the Austrian Netherlands1795: To France1815: To the Netherlands1830: To Belgium Mecklenburg Principality1347: Duchy n/a n/a 1167: Obotrite prince became a vassal of Saxony, known then on in Germany as Mecklenburg1180: Imperial immediacy1234: Partitioned into itself, Werle, Rostock and Parchim-Richenberg1255: Acquired Sternberg1301: Acquired Wismar1304: Acquired Stargard1312: Acquired Rostock1319: Acquired Prignitz and Uckermark1325: Lost Prignitz and Uckermark1347: HRE Duke1352: Partitioned into Mecklenburg-Schwerin and Mecklenburg-Stargard Mecklenburg-Grabow Duchy n/a n/a 1669: Appanage created in Mecklenburg-Schwerin1747: Inherited Mecklenburg-Schwerin; appanage abolished Mecklenburg-Güstrow Duchy Low Sax PR 1480: Partitioned from Mecklenburg-Schwerin1483: Extinct; to Mecklenburg-Schwerin1520: Partitioned from Mecklenburg-Schwerin1610: Extinct; to Mecklenburg-Schwerin1621: Partitioned from Mecklenburg-Schwerin1628-31: To Wallenstein1695: Extinct in male line; succession dispute1701: Ratzeburg and Stargard to Mecklenburg-Strelitz; rest to Mecklenburg-Schwerin Mecklenburg-Mirow Duchy n/a n/a 1658: Appanage created in Mecklenburg-Schwerin1675: Extinct; to Mecklenburg-Schwerin Mecklenburg-SchwerinGrand Duke of Mecklenburg, Prince of the Wendes, Schwerin & Ratzeburg, Count of Schwerin, Lord of the Lands of Rostock and Stargard Duchy1815: Grand Duchy Low Sax PR 1352: Partitioned from Mecklenburg1358: Acquired Schwerin1480: Partitioned into itself and Mecklenburg-Güstrow1436: Acquired 1/3 of Werle1520: Partitioned into itself and Mecklenburg-Güstrow1552: Succession dispute1556: Given to John Albert I, co-Duke of Mecklenburg-Güstrow1621: Partitioned into itself and Mecklenburg-Güstrow1628-31: To Wallenstein1648: Acquired the Bishopric of Schwerin1658: Appanage Mecklenburg-Mirow1669: Appanage Mecklenburg-Grabow created1815: Grand Duchy Mecklenburg-Stargard Duchy n/a n/a 1352: Partitioned from Mecklenburg1408: Partitioned into Mecklenburg-Stargard-Sternberg and Mecklenburg-Stargard-Neubrandenburg1438: Reunited by Mecklenburg-Stargard-Neubrandenburg1471: Extinct; to Mecklenburg-Schwerin Mecklenburg-Stargard-Neubrandenburg Duchy n/a n/a 1408: Partitioned from Mecklenburg-Stargard1436: Acquired 1/3 of Werle1438: Renamed to Mecklenburg-Stargard Mecklenburg-Stargard-Sternberg Duchy n/a n/a 1408: Partitioned from Mecklenburg-Stargard1436: Acquired 1/3 of Werle1438: Extinct; to Mecklenburg-Stargard-Neubrandenburg Mecklenburg-StrelitzGrand Duke of Mecklenburg, Prince of the Wendes, Schwerin and Ratzeburg, Count of Schwerin, Lord of the Lands of Rostock and Stargard Duchy1815: Grand Duchy Low Sax PR 1701: Created from Ratzeburg and Stargard from Mecklenburg-Güstrow for Adolphus Frederick II1