Complex sentence: Although Genghis Khan "did not disturb the inhabitants (of the city) in any way", according to Juvaini he killed all who took refuge in the citadel and the mosque, pillaged the city completely and conscripted 30,000 young men along with 30,000 craftsmen.
Split into simpler sentences: Although Genghis Khan "did not disturb the inhabitants (of the city) in any way", according to Juvaini he killed all who took refuge in the citadel and the mosque. He also pillaged the city completely and conscripted 30,000 young men along with 30,000 craftsmen.