| Name | Type | Circle | Bench | Formed | Notes |
| Tanegg | Vogtei | | | | |
Tarasp Trasp | HRE Lordship | Aust | | | 1512: Austrian Circle 1683: To Princes of Dietrichstein |
| Teck | Duchy | Swab | | | 1381: Sold their lands to the Counts of Wurttemberg; the title of Duke of Teck was in 1495 the basis for the elevation of the county of Wurttemberg to a duchy |
| Tecklenburg | County | Low Rhen | WE | Early 11th century | 1189: Simon of Tecklenburg acquired the Lordship of Ibbenburen 1263: Annexed by Bentheim 1327-1557: To Counts of Schwerin 1365: Acquired Lordship of Rheda 1385: Acquired Lordship of Iburg 1493: Division into Tecklenburg (with Rheda) and Lingen 1557: Tecklenburg and Rheda to Bentheim 1696: Tecklenburg to Solms-Braunfels by judgment 1707: Solms-Braunfels sold rights to Brandenburg 1808: To Grand Duchy of Berg<1810>To France 1815: To Prussia |
| Tettnang and Argen | HRE County | | | | 882. 1st mention of Tettnang |
| Thannhausen | Lordship 1665: HRE County | | | | 1708: Acquired by Stadion To Sinzendorf |
Thengen (Tengen) | Lordship 1663: Imperial County | Swab | | | To Habsburg dominions in Swabia 1663: To the Prince of Auersperg which gave him a seat and a voice in the Reichstag |
| Thorn | 992: Abbacy 1292: Imperial Principality-Abbacy | Low Rhen | | 992 | 1793: Council of Princes 1795: Annexed to France 1815: To The Netherlands |
| Thüngen | Lordship | | | | |
| Thurgau | Landgraviate | | | | |
| Thuringia | 1130: Landgraviate | | | | 1247: Male line died out |
Thurn and Taxis HRE Prince of Thurn & Taxis, Prince of Buchau, Princely Count of Friedberg & Sheer, Count of Valsassina/Valle-Sassina, Baron of Impden, Lord of the free Imperial Lordships of Eglingen & Osterhofen, of Lordships of Demmingen, Markt-Dischingen, Trugenhofen, Ballmertshofen, Duttenstein, Wolfertheim, Rossum & Meusseghem | 1608: HRE Barony 1624: HRE Count 1695: HRE Principality | | | | 1512: Granted noble status by Emperor Maximilian I (confirmed in 1534 by Emperor Charles V) 1512: To Electoral Rhenish Circle 1615: Lamoral von Taxis appointed hereditary Imperial Postmaster General 1681: Granted princely rank in the Spanish Court Acquired Eglingen 1754: HRE Council of Princes |
| Thurnau | Lordship | | | | |
| Toggenburg | 1209: County | | | | 1044: 1st mention of Counts of Toggenburg 1394: Division 1468: Sold to Abbacy of St Gall |
| Toul | 300's: Bishopric | Upp Rhen | | 1048 | 1552: Annexed to France 1648: Formally ceded to France |
| Toul | Imperial City | Upp Rhen | | | Annexed to France in 1552 |
Trauttmansdorff Prince of Trauttmansdorff-Weinberg and Neustadt am Kocher, Princely Count of Umpfenbach, Baron of Gleichenberg, Nogau, Burgau and Totzenbach, etc. | 1623: HRE County 1805: HRE Principality | | | | 1300s: Family 1st mentioned Acquired Weinsberg and Neustadt |
Trent Trento / Trient | c300: Bishopric 1027-1802: HRE Prince-Bishopric | Aust | EC | 1027 | 1300s: Annexed to Bavaria 1363: Bishops gave County of Tyrol to Rudolf IV of Austria 1419: Bishop submitted directly to Emperor 1425: Trento declared a commune Trento and Brizen received status of "[er[etual confederate" states among Austrian possessions 1512: Austrian Circle c1519: Bishops acquired lordships of Castelbarco and Rovereto 1578:Prince-Bishops re-acquired sovereignty To 1658: Trento and Brixen held by Madruzzo family 1658: Assigned to Sigismund Francis, Regent of Tirol 1662: Under direct Imperial rule 1793: Council of Princes 1801: Secularized and annexed by Austria 1803: Incorporated into Austria as part of Tyrol 1805: Annexed to Bavaria 1810: Annexed to Kingdom of Italy 1813: Annexed to Austria<1918>Annexed to Italy |
Triest Trieste | 1295: Free Imperial City | | | | Till 1285: To Bishopric of Trieste 1382: Accepted Austrian (Leopoldine line) ovelordship 1806-1813: French rule |
| Triberg | Lordship | | | | |
| Trier | c811: Archbishopric 1356: HRE Prince-Elector | El Rhin | EL | 898 771: Autonomous | 898: Trier obtained its temporal power under Archbishop Radbod from Duke Zwentibold of Lorraine 1512: Electoral Rhenish Circle 1803: Annexed to Nassau-Weilburg |
| Troppau (Opava) | Principality | n/a | n/a | 1278 | 1366: Partitioned into Troppau-Leobschütz, Troppau-Ratibor and Troppau-Troppau |
| Troppau-Jägerndorf | Principality | n/a | n/a | 1424: Partitioned from Troppau-Ratibor | 1433: Partitioned into itself and Troppau-Rybnik 1474: Annexed to Bohemia |
| Troppau-Leobschütz | Principality | n/a | n/a | 1366: Partitioned from Troppau | 1394: Annexed to Bohemia 1433: Partitioned from Troppau-Troppau 1462: Annexed to Bohemia |
| Troppau-Münsterberg | Principality | n/a | n/a | 1433: Partitioned from Troppau-Troppau | 1452: Partitioned into itself and Troppau-Steinau 1464: Annexed to Bohemia |
| Troppau-Ratibor | Principality | n/a | n/a | 1366: Partitioned from Troppau | 1424: Partitioned into itself and Troppau-Jägerndorf 1506: Annexed to Bohemia |
| Troppau-Rybnik | Principality | n/a | n/a | 1433: Partitioned from Troppau-Jägerndorf | 1424: Partitioned into itself and Troppau-Jägerndorf 1479: Annexed to Bohemia |
| Troppau-Steinau | Principality | n/a | n/a | 1433: Partitioned from Troppau-Troppau | 1474: Annexed to Bohemia |
| Troppau-Troppau | Principality | n/a | n/a | 1366: Partitioned from Troppau | 1433: Partitioned into Troppau-Leobschütz and Troppau-Münsterberg |
| Tubingen | HRE County | | | | |
Turckheim Turkheim | Imperial Free City | Upp Rhen | | | Annexed to France in 1648 |
Tyrol Tirol | 1140: County 1493: Princely County | Aust | PR | 10th century? | 1363: To Habsburgs 1512: Austrian Circle 1582: HRE Council of Princes 1802: Bishopric of Trent secularized and annexed to Tyrol Trent, Tyrol and Voralberg ceded to Bavaria |