Lubny, city and port, east-central Ukraine, on the Sula River. Lubny was established in the late 10th century as a fortified Rus town. It was destroyed by the Mongols in 1239 and was not rebuilt until the 16th century. From the mid-17th century to 1781, it was a regimental centre in the Cossack-controlled state known as the Hetmanate; it then came under direct Russian administration. The city’s industries have included textiles, clothing, furniture, and construction. Pop. (2005 est.) 50,232.