The Battle of Poltava (June 27, 1709)
Ukrainian: Полта́вська би́тва) on 27 June 1709 was the decisive victory of Peter I of Russia, also known as Peter the Great, over the Swedish forces under Field Marshal Carl Gustav Rehnskiöld, in one of the battles of the Great Northern War.
It is widely believed to have been the beginning of Sweden's decline as a Great Power, as the Tsardom of Russia took its place as the leading nation of north-eastern Europe. The battle also bears major importance in Ukrainian national history, as Hetman Ivan Mazepa sided with the Swedes, seeking to create an uprising in Ukraine against the tsardom.
References:
https://en.wikipedia.org/wiki/Battle_of_Poltava
https://en.wikipedia.org/wiki/Charles_XII_of_Sweden
Voltaire and Mazepa's Ukraine
Although Voltaire never penned a separate essay or historical work specifically about Mazepa's Ukraine, he did touch upon this land in two very different histories dealing with eastern Europe, or "le nord," or "l 'Europe septentrionale," as it was then usually called. The first is his Histoire de Charles XII roi de Suede (1731) which was his first important historical work and a great success, reprinted many times during his lifetime and many more afterwards. This history described the military exploits of the young and warlike king of Sweden whose career took him from Scandinavia through parts of Germany and the vast Polish-Lithuanian Commonwealth, and after many great victories, into Ukraine where he suffered his first great defeat at the hands of the Russians, or "Muscovites" as they were then usually known. This defeat occurred at the Battle of Poltava (1709) in the eastern part of that country. …
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