| Type: | Cardinal |
| Honorific Prefix: | His Eminence |
| Maria Thaddäus von Trautmannsdorff | |
| Cardinal, Archbishop of Olomouc | |
| Church: | Roman Catholic Church |
| See: | Olomouc |
| Appointed: | 23 September 1816 |
| Predecessor: | Antonín Theodor Count of Colloredo-Waldsee |
| Successor: | Archduke Rudolf of Austria |
| Other Post: | Bishop of the Roman Catholic Diocese of Hradec Králové |
| Cardinal: | 23 September 1816 |
| Created Cardinal By: | Pope Pius VII |
| Birth Date: | 28 May 1761 |
| Birth Place: | Graz |
| Death Place: | Vienna |
| Buried: | Olomouc |
| Coat Of Arms: | COA_cardinal_AT_Trautmannsdorff_Maria_Thaddaus.png |
| Cardinal Name: | Maria Thaddäus von Trautmannsdorff |
| Dipstyle: | His Eminence |
| Offstyle: | Your Eminence |
| See: | Olomouc |
Maria Thaddäus von Trautmannsdorff (28 May 1761 - 20 January 1819) was a cardinal of the Roman Catholic Church.[1]
He was born on 28 May 1761 in Graz as son of Imperial Count Weikhard Joseph von Trauttmansdorff-Weinsberg (1711-1788) and Countess Maria Anna von Wurmbrand-Stuppach (1733-1807).
He was ordained as Bishop of Hradec Králové on 8 September 1795.[2] On 26 November 1811 he was elected Archbishop of Olomouc. Due to the imprisonment of Pope Pius VII by Napoleon Bonaparte, papal approval of this decision did not take place until 15 March 1814. On 23 September 1816 he was appointed cardinal.[3]
He died in Vienna on 20 January 1819 and was buried in Olomouc.[1]