Vietnam was dominated by China's Han Dynasty from 100 BC until around 900 AD, when it gained independence. The Vietnamese culture was influenced by Chinese culture, and a new capital, Hanoi, was established by the Ly Dynasty between 1009-1225. Vietnam expanded by conquering neighboring peoples, and resisted three Mongol invasion attempts between 1257-1287. The Khmer Empire, based in modern-day Cambodia, became powerful around 1200 due to rice cultivation and irrigation systems. The Khmer capital of Angkor featured elaborate cities and temples, and the Khmer expanded through conquering neighboring kingdoms under the Sailendra dynasty.