The town of Brahea was founded in 1653 by Pietari Brahe, in the early 1680s the town was suppressed. On 1 January 1936 the Borough of Lieksa was separated from the Municipality of Pielisjärvi. On 1 January 1973 the Borough of Lieksa and Municipality of Pielisjärvi were again merged and the City of Lieksa was founded.

The city of Lieksa is situated in the province of East Finland, in the north-eastern part of North Karelia on the shores of Lake Pielinen. The 6th largest lake in Finland, Pielinen divides the city in two; on the western shore rises the magnificent hill range of Koli and the eastern shore lies the population centre of the city and the natural wilderness, which extends all the way to the eastern border of Filnland.