In 1368, a rebellion led by Zhu Yuanzhang broke out in southern China, and eventually overthrew the Yuan Dynasty. Then Zhu Yuanzhang founded the Ming Dynasty at Nanjing, its capital until Emperor Yongle changed the capital to Beijing. In the 15th century, a man named Zheng He took the majority of the Ming navy and explored the Indian Ocean, and brought wealth and power to the Ming Dynasty. The empire experienced a prosperous period until 1449, when the Battle of Tumu Fortress broke out. In the battle the Mongol descendants of Yuan captured the emperor and surrounded the capital. After the war with the Mongols, the Ming started to decline. During this time, the empire had two wars with the Japanese (the first against the Japanese pirates took place at southeastern China; the second against the armies of Toyotomi Hideyoshi that invaded Korea), and one war with the Portuguese of Macao. These wars eventually weakened the declining empire. In 1616, rebellions broke out at Manchuria and Shanxi. Twenty-eight years later, the Manchus crossed the Great Wall, invaded the capital, and destroyed the Shanxi rebels.