From the back cover:
Poltava marked the demise of Sweden as a European great power and the rise of Russia. In 1707, the seemingly invincible Charles XII led his army deep into Russia. It was to prove his undoing - the long march eroded the fighting strength of the invaders; a vital supply convoy was lost; and the winter of 1708/9 was the worst in living memory. Drawing upon primary source material previously unseen in the west, Angus Konstam recounts the events, looking in particular at how this battle led to the destruction of the Swedish Army.