In the twelfth century, the hillfort of the Balts tribe of Selonians functioned on the site of a later castle. Probably around 1208 it was subjugated to the crusaders. After the strengthening of the Christian rule, Selburg was planned as the capital of Selonia’s bishopric only existing in the years 1218-1225. This project has not been implemented, and the bishopric itself changed its name from 1225 to the diocese of Semigallia and in 1251 it was liquidated.
Serious investments of the Teutonic Order in Selburg did not take place until 1373, when the older wood and earth ramparts were replaced with stone fortifications. Probably also then the castle was raised to the rank of a teutonic vogt, although the first recorded name of this official comes from 1422-1423, when Eberhard von Altena was in Selburg. The main task of the castle was control of trade and safety of navigation on the river Daugava and protection of the border with Lithuania and the Archbishopric of Riga.
After the decline of the Livonian branch of the Teutonic Order, the rule over the castle was taken over by the Duchy of Courland and Semigallia, dependent on the Polish-Lithuanian Commonwealth. The stronghold was then expanded, thanks to which it retained its military significance. During the Polish-Swedish wars from the first half of the 17th century, Selburg was passed from hand to hand. The end of the castle took place in 1704. During the Great Northern War, Selburg was blown up by the Swedes and was never rebuilt.
The castle built on the river island had an irregular shape adapted to the form of the terrain and earlier wood and earth ramparts, so it did not refer to the model of Teutonic Order conventual architecture. The stone defensive wall was reinforced with at least a few defensive towers.
The relics of the castle are located on a hard-to-reach island on the river Daugava. Originally it was on a hill, but today, due to the construction of the dam and raising the level of water on the river, it is located next to the shore.
Borowski T, Miasta, zamki i klasztory, Inflanty, Warszawa 2010.