By 1650, Koxinga was strong enough to establish himself as the head of the Zheng family. He pledged allegiance to the only remaining claimant to the throne of the Ming Dynasty, the Yongli Emperor. The Yongli Emperor was fleeing from the Manchus in south-western China with a motley court and hastily assembled army at the time. Despite one fruitless attempt, Koxinga was unable to do anything to aid the last Ming emperor. Instead, he decided to concentrate on securing his own position on the southeast coast.