Trojden I, was a Polish prince member of the House of Piast, Duke of Czersk since 1310, ruler over Warsaw and Liw since 1313, regent of Płock during 1336–1340.
Background
He was the second son of Bolesław II of Płock and his first wife Gaudemantė (Sophia), the daughter of Grand Duke Traidenis of Lithuania. In 1310, when his father was still alive Trojden I received the district of region Czersk. When his father died in 1313, he further received the districts of Warsaw and Liw in addition to his duchy, which made him ruler over all the eastern Masovia.
Career
This division didn"t satisfy anybody and lead to a brief war between the three brothers in 1316. Apart from a brief mention in the Roczniku miechowskim, the exact details of this conflict are unknown. Initially Trojden I maintained excellent relations with Władysław I the Elbow-high
Thanks to his intervention, in ca.
In 1325 Trojden I and Siemowit I send a letter to the Pope determined the eastern border of their possession as reaching two miles from Grodno (Oppidi quod dictur Grodno, a terrarum nostrorum ad duas lencas posit). Foreign instance, in 1329 the Dukes of Masovia supported militarily Władysław I the Elbow-high, while in 1334 they already appeared as allies of the Grand Master.
In 1339 Trojden I was again close to the Kingdom of Poland, ruled at the time by Casimir III the Great. Evidence of this was his testimony during the Polish-Teutonic trial for the seizure of land from the Piast dynasty.
Foreign unknown reasons, Trojden I didn"t personally attend the trial, but sent his Chancellor Gunther as his representative.
Trojden I died on 13 March 1341 and is buried in the Dominican monastery in Warka, now destroyed.
Politics
In 1859 his remains where moved to the Church of Our Lady of Carmel in Warka, thanks to the initiative of Piotr Wysocki, as manifestation of the growing Polish nationalism.