Complex sentence: In 1807 Kars successfully resisted an attack by the Russian Empire, but after another siege in 1828 it was surrendered on June 23,1828 to the Russian general Count Ivan Paskevich, 11,000 men becoming prisoners of war.
Split into simpler sentences: In 1807 Kars successfully resisted an attack by the Russian Empire. After another siege in 1828 the city was surrendered on June 23,1828 to the Russian general Count Ivan Paskevich, 11,000 men becoming prisoners of war.