sentences:  Russian forces managed to penetrate Ingria and established a new city, Saint Petersburg, there.Charles planned an invasion of the Russian heartland, allying himself with Ivan Mazepa, Hetman of the Ukrainian Cossacks.The size of the invading Swedish army was peeled off as Charles left Leszczyński with some 24,000 German and Polish troops, departing eastwards from Saxony in late 1707 with some 35,000 men, adding a further 12,500 under Adam Ludwig Lewenhaupt marching from Livonia.