Initially a small Hutsul settlement with a remnants of a small castle destroyed by the Turks. It was founded at Rybnica River. The first written mention of it is in the Grant Charter of Prince Svydryhaila Vlady Drahasynovycha, on September 31, 1424. At that time, the village was in the territory of what is today Old Kosiv. In 1565, near the slattern, not far from modern-day Kosiv, Snyatynskyi Starosta Tenchunskyi founded a town named Rukiv. Sir Yazlovetskyi, the head of Kuty, later destroyed it. Some years later, the town was recovered and named Kosiv (the earlier village of this name thus became Old Kosiv). Until 1772, Kosiv was under Polish control. As a result of the first of Partitions of Poland (Treaty of St-Petersburg dated 5 July 1772), Kosiv (and the Galicia) was attributed to the Habsburg Monarchy. For more details, see the article Kingdom of Galicia and Lodomeria.
Since 1867, Kosiv has been the administrative center of the Kossow Bezirkshauptmannschaft (Austrian name of the district).
In 1919, after the Great War the area returned to Poland and was turned into a powiat seat within the Stanis?aw�w Voivodship. In 1939, Western Ukraine became part of the Union of Soviet Socialist Republics (USSR) as a result of the Molotov-Ribbentrop Pact. Despite this pact, Kosiv was occupied by Nazi Germany from July 1,1941 until April 2, 1944. After that time it was, again, a member of the Soviet Union, until the independence of Ukraine
