[8] Buy was originally a trading post and protected by a hill fortress of Finno-Ugrian Meri people c. 400–500 CE.

The fortified point was built according to the order of Yelena Glinskaya, the regentess of Russia at that time and the mother of Ivan the Terrible, to defend the eastern frontiers of the Grand Duchy of Moscow from the raids by Kazan Tatars and others.

Cottage industries included pottery, iron, leather, felt, wool, carpentry, painting, blacksmithing, and oil pressing.

The soft bog water allowed the plant to produce a high-quality product which was sold even in provincial capitals.

In 1914-1915 the Russians built a large POW camp for captured Austrian, Hungarian, and German prisoners of war.

It was located 3 versts (3.2 km) south of Buy in Korega at the west bank of Kostroma River.