Happy Birthday, Ivan
Іван Степанович Мазепа - Ivan Mazepa - was born today, in what is now called Mazepyntsy, near Bila Tserkva in Ukraine around 1640. The usual English spelling of his name is Mazeppa, which is from the Russian.
Mazepa was an ambitious Kozak (Cossack) officer who rose quickly through the ranks in the post-Pereyaslavl Left Bank Hetmanate (the 1653 Treaty of Pereyaslavl between Hetman Bohdan Khmelnytskyy and Tsar Alexey I of Muscovy was fraught with misunderstandings from the beginning). Mazepa began as a loyal ally of Russia (as Muscovy was now called under Peter I, the Great), and became hetman in 1687 after accusing his predecessor, Samoylovych, of planning to break the treaty and secede from Muscovy. In 1702 Mazepa crossed the Dnipro (Dneiper) and annexed large portions of Right-Bank Ukraine after Semen Paliy's failed uprising against the Poles, establishing him as a wealthy and powerful ruler.
But the Great Northern War wasn't good to Russia - the Swedes and Lithuanians were a serious force back then - and Peter I decided to take steps - steps Mazepa saw as threatening the Hetmanate's autonomy. Peter I began sending Kozaks to fight in foreign wars, instead of leaving them to defend Ukraine against Tatars and Poles (as the treaty stipulated). Kozak soldiers were neither equipped nor trained for modern warfare, and they were often commanded by Russians and Germans who often did not much value their lives. They suffered loss of morale, and heavy casualties, while at home a Russian force became an oppressive occupier.
In 1708, Polish King Stanislaus Leszczynski, an ally of Charles XII of Sweden, threatened to attack the Hetmanate. Peter I refused to defend Ukraine, expecting an attack on Russia proper by Charles XII. In Mazepa's opinion, this blatantly violated the Treaty of Pereyaslav, since Russia refused to protect Ukraine's territory and left it to fare on its own. As the Swedish and Polish armies advanced towards Ukraine, Mazepa allied himself with them on October 28, 1708.
The Russian army responded by razing the Kozak capital Baturyn, killing the defending garrison and all of its population. The Russian army was ordered to tie up the dead Kozaks to crosses, and float them down the Dnieper River all the way to the Black Sea with the goal of scaring all the people loyal to Mazepa who lived along the river.
The Battle of Poltava, June 29, 1709, was won by the Russians (a victory which shook Europe and established Russia as a true imperial force and power player in European politics), and this destroyed Mazepa's hope for an independent Ukraine. He fled along with Charles to refuge in Bendery, among the Turks, where he died soon afterwards. The tsars began to dismantle the Hetmanate, and by 1764 the largely puppet remains of it were abolished.
Mazepa's legacy during Russian rule of Ukraine, and Soviet rule thereafter, was one of treason and revilement. He was excommunicated by the Orthodox Church, Tchaikovsky's opera "Mazeppa" casts him as the villain, and any positive view of him was "Ukrainian bourgeois nationalism", a serious crime in Soviet days. But since Ukrainian independence the hetman's memory has enjoyed a resurgence, and he is recognized as a national hero.
He's even on the money.