Shah Jahan was the third son of emperor Jahangir and became emperor himself in 1628 after gaining support from his wife's family. As emperor, he had military successes expanding Mughal power in southern India and the northwest. However, some territories like Kandahar were later lost back to Persia. Shah Jahan is most famous for his passionate interest in architecture and magnificent buildings like the Taj Mahal, as well as structures in the Red Fort complex in Delhi.