For the first time in chronicles, the city of Mir is mentioned under 1359, in connection with the ruin of local lands by the army of the crusaders.
In 1490, the city departed the princely genus Ilinichy. At the end of the 15th century Yuri Ilinich began construction of a stone castle in the Mir. The fortress was of unusual construction. Corner and portal towers were taken out beyond the outer outline of the defensive walls. The presence of gun fighters along the perimeter indicates the unique strengthening of the castle of those times. The towers were equipped with special holes, through which hot resin, boiling water or stones were poured on the soldiers depositing the fortress. There was a complex system to block entry. The single system included a wooden lifting grille fortified with iron, two gates made of oak massif and a lifting bridge. On the west and north sides, the walls were equipped with upper combat galleries. On the tops of the towers there were many fighters directed in different directions, made for light firearms. The crossings between the defensive towers on the walls and the battle galleries were designed to confuse the enemy first caught there.
Genus of Ilinichy owned the castle for three generations. In 1568, the last Prince Ilinichy died and had leaved no heir. The local lands were transferred to the possession of cousin Nikolai Krishtof Radziwil.
The castle was repeatedly modernized and rebuilt by new owners.
Additional protection was given by building of earth shafts with bastions. Some fragments of the facade of the building were changed.
The castle complex was involved in almost all wars, during which it was repeatedly damaged and restored.
From 1812 the badly damaged castle remained in disuse. After the division of Radziwill’s property repeatedly changed owners.
Restoration of the complex began in 1983. The work was completed by 2000. The castle is listed as a UNESCO World Cultural Heritage Site.