Thien Mu Pagoda was built in 1601 CE under Nguyen Hoang, the governor of Thuan Hoa province, now known as Hue. Although he swore loyalty to the Le Dynasty in Hanoi, Nguyen Hoang effectively ruled Thuan Hoa as an independent state in central Vietnam. The pagoda has seven storeys and is the tallest in Vietnam, and is often the subject of folk rhymes and poetry about Hue, which was the imperial capital of Vietnam between 1802 and 1945. Hue was the imperial capital of the Nguyen Dynasty between 1802 and 1945. The tombs of several emperors lie in and around the city and along the Perfume River. Hue is a UNESCO World Heritage Site.