From about 1100 it began to expand into northern India as far as Bengal, gradually supplanting the declining Indo-Sassanid Empire as the dominant power in the region. Later shahs even set up secondary capitals at Lahore and Delhi, which were mainly used in the winter. However, just a few years later the Shansabanids themselves were almost wiped out in a lightning campaign by Genghis Khan. Shah Firuz V fled to his Indian territories and tried to rebuild his strength, but Delhi too had been conquered by 1265. The Shansabanid territory was divided between the khanates of Chagatai and Delhi.