Duke Juryj Ivanavič Illinič (pl:Jerzy Iwanowicz Ilinicz) began construction of the castle near the village of Mir after the turn of the 16th century in the Polish Gothic style. Five towers surrounded the courtyard of the citadel, the walls of which formed a square of 75 metres (246 ft) on each side. In 1568, when the Ilyinich dynasty died out, the Mir Castle passed into the hands of Mikołaj Krzysztof "the Orphan" Radziwiłł, who refitted it with a two-winged, three-story stately residence along the eastern and northern inner walls of the castle.