In autumn 1621, at a fortified camps near Khotyn (Chocim), in Principality of Moldavia, joint Polish, Lithuanian and Cossack armies faced large Ottoman army, led by Sultan Osman II. It was conclusion of the war that started with the defeat of Polish army at Cecora one year earlier,. As such it was in fact part of the longer conflict, waged over Commonwealth’s and Ottoman’s influence over Moldavia. Through the whole September and first half of October 1621, allied army managed to defend their camps against Turks, with both sides taking heavy losses due to the hardship of the siege operations and worsening weather conditions. Conflict ended with the Treaty of Khotyn (9 October 1621) which didn’t favored any of the sides. At the same time, stopping the Ottoman was seen as a big success for the Commonwealth, while attitudes on the Ottoman sides were far from victorious. Aftershock of the war led to the rebellion of janissaries in 1622, resulting in dethroning and murder of Sultan Osman II.Book focuses on the Khotyn campaign of 1621, describing day-by-day actions of fighting armies – assault, sallies and raids - during the whole period of the siege. Additional theaters of war, like Cossack operations from the summer 1621 and Tatars raids against Polish inland, are mentioned as well. Readers can find here details of the organization and strength of the fighting armies, information about battle disposition of the troops present at Khotyn and commanders leading the troops. Actions leading to the outbreak of the open conflict are explained in the separate chapter, providing good historical background of the war. Another one covers the outcome of the war and the ways that influence internal and external situation of both the Commonwealth and the Ottoman Empire.As with his previous works, author utilized large number of primary sources: from diaries of soldiers taking part in the campaign, through chronicles from period, official letters and documents to army musters. Amongst used documents are not only those written by Poles and Lithuanians, but also Cossacks, Germans and Ottomans. Modern works, especially from Polish and Ukrainian historians, was used as well, in order to provide the most up-to-date and in-depth research. As this topic do not have much coverage in English, it should be valuable addition to the collection of anyone interested in the history of Polish-Lithuanian Commonwealth, Zaporozhian Cossacks and Ottoman Empire in the early 17th century.