The Tang Dynasty was an imperial dynasty that was preceded by the Sui Dynasty and followed by the Five Dynasties and Ten Kingdoms Period. It is generally regarded as a high point in Chinese civilization and a golden age of cosmopolitan medieval Chinese culture. Its territory, acquired through military campaigns, rivaled that of the Han Dynasty 汉朝, and the Tang capital at Chang'an 长安 (about present-day Xi'an 西安) was the most populous city in the world of that time.