Dzierzgoń 'dźe1żgoń (formerly also: Kiszpork; Christburg) is a town in the Pomeranian Voivodeship in northern Poland. It is located in Sztum County east of Malbork and south of Elbląg on the river Dzierzgoń. Dzierzgoń has a population of 5,242, while the town and its environs have a combined population of about 10,000. The town was originally a settlement of Old Prussian tribe of Pomesanians. Settlement dates back to the Early Middle Ages. The oldest name is Sirgune, from which the historic Polish name Dzierzgoń comes from. In 1247, a castle known as Neu Christburg (German for "New Castle of Christ") was founded overlooking the Dzierzgoń river, a few kilometers away from an older fortress known as Alt Christburg (Stary Dzierzgoń) by Teutonic Knights brought to Poland by Konrad I of Masovia. In 1249 a peace treaty was signed at the new castle between the victorious Teutonic Order and defeated local Old Prussians, in presence of papal legate, future Pope Urban IV. In 1254, the town which had developed near the castle was first referred to as Christburg (in Polish known as Kiszpork). Within the Monastic State of the Teutonic Order, Christburg was an administrative seat for the regional Komtur. Both Polish and German settlement began around 1280. By 1288 the settlement was granted town rights. Following the victorious Battle of Grunwald, in 1410, Polish King Władysław II Jagiełło stayed in castle, after it was abandoned by the Teutonic Knights. In the castle, the king received delegations from the city of Elbląg, which then pledged allegiance to him and recognized his authority. In 1411, the Poles left the castle, and the Teutonic Knights retook it. The castle was captured by Poles again in 1414. In 1454, upon the request of the anti-Teutonic Prussian Confederation, the town was incorporated into the Kingdom of Poland by King Casimir IV Jagiellon, and the castle was handed over to Poland. The town sided with Poland in the subsequent Thirteen Years' War, after which in the 1466 peace treaty the Teutonic Knights renounced any claims to the town.