Trojden I of Masovia (1284 or 1286 – 13 March 1341) was a member of the House of Piast. He was Duke of Czersk from 1310. From 1336 to 1340 he was Regent of the Duchy of Płock. He eventually became Duke of Masovia.
Trojden was the second son of Boleslaus II of Masovia and his first wife, Sophie, the daughter of Grand Duke Traidenis of Lithuania.
In 1310, when his father was still alive Trojden received the small region Czersk. When his father died in 1313 he inherited parts of Warsaw and Liw in addition to his duchy, which allowed Trojden to reign over Eastern Masovia.
Initially Trojden maintained excellent relations with Ladislaus the Short, king of Poland. Thanks to his intervention, in 1310 Trojden married Maria, daughter of Yuri I of Galicia and Euphemia of Kuyavia (Trojden's cousin). When Roman the Great died, there ware two heirs. Ladislaus supported Boleslaus, the son of Trojden, who seized the throne and took the name of George II (Jerzy II).
The aggressive policy pursued by Ladislaus the Short to reunite the territories of Poland and Masovia were a threat. On January 2 1326 at Brodnica, Trojden and his brothers, Siemowit II of Masovia and Wenceslaus of Płock concluded an agreement with the Teutonic Knights, which lead to a short conflict with Poland and its ally Lithuania.
In 1340, his eldest son Boleslaw (aka George II) was murdered by his subjects. Trojden waives his right to succeed his son in exchange for a large sum of money paid to him by Casimir III the Great.
Trojden died on March 13 1341 and is buried in the church of Dominicans in Rawa.
Before 1310, Trojden married Maria daughter of Yuri I of Galicia, they had four children[1]:
| Preceded by Siemowit II of Masovia |
Duke of Eastern Masovia 1310-1341 |
Succeeded by Casimir I of Warsaw |