中国人民解放军第四野战军
By the winter of 1948, the balance of power in Northern China was shifting in favor of the People's Liberation Army. As the Communist Fourth Field Army led by Lin Biao and Luo Ronghuan entered the North China Plain after the conclusion of the Liaoshen campaign, Fu Zuoyi and the Nationalist government in Nanjing decided to abandon Chengde, Baoding, Shanhai Pass and Qinhuangdao collectively and withdraw the remaining Nationalist troops to Beiping, Tianjin and Zhangjiakou and consolidate the defense in these garrisons. The Nationalists were hoping to preserve their strength and reinforce Xuzhou where another major campaign was under its way, or alternatively to retreat to the nearby Suiyuan Province if necessary.