Marquess Wen wanted to take control of the State of Zhongshan but in order to attack, he needed access through the State of Zhao. The rulers of Zhao at first refused the Marquess’ request but when the Zhao Chancellor heard he said: "If Wei attack Zhongshan and they are defeated, they are bound to have lost a significant portion of their resources and will become a weak country. If on the other hand they annihilate Zhongshan, the new territory will be bisected by our country and it will be difficult for Wei to remain in control of it for any significant period." On hearing this the Zhao ruler Zhào Xiàn-zǐ () agreed to allow the Wei army to pass through the Zhao State.