In February 1935, before Xie Zichang died, Liu Zhidan went to visit him. The two had a long talk and decided to unite the two base areas in northern Shaanxi and Shaanxi-Gansu border areas as soon as possible to strengthen the Shaanxi-Gansu Red Army and the base areas.The Kuomintang army launched a large-scale encirclement and suppression campaign against Nanliang. Xi Zhongxun single-handedly attracted the enemy and cooperated with Liu Zhidan to divert the masses and contain the enemy.Gu Lin and other comrades who were influenced by the %Leftist line carried out a land inspection campaign in the Nanliang area, and there was a problem of misidentification of ingredients. Xi Zhongxun and others promptly stopped it after discovering it.In September 1935, the Shaanxi-Gansu Red Army and the 25th Red Army joined forces to form the 15th Red Army and won the Battle of Laoshan.The Central Red Army arrived at Hadapu during the Long March. Mr. Mao discovered the news about the Red Army in northern Shaanxi from the newspapers, and finally decided to go to northern Shaanxi to find Liu Zhidan.