During the reign of Emperor Daizong, Liang took advantage of the army's discontent after the death of the general Lai Tian (來瑱) to seize control of Shannan East Circuit (山南東道, headquartered in modern Xiangfan, Hubei) and held it semi-independently from the imperial regime.
He became an archer in the imperial guards and later served under the general Lai Tian in Tang's struggle against rebel Yan forces during the Anshi Rebellion.
During this time, Lai became hesitant to periodically visit Chang'an to pay respect to Emperor Suzong, because of his poor relationships with the powerful eunuchs, led by Li Fuguo.
After Li Fuguo was removed from power later in the year, however, Lai accepted honorary titles as the minister of defense and chancellor and reported to Chang'an to meet Emperor Daizong.
Neither he nor two other officers, Li Zhao (李昭) and Xue Nanyang (薛南陽), was initially willing to claim leadership, but the soldiers supported him, and so he took command.
Therefore, as Li Zhou reached the borders of Shannan East, Liang refused him entry and requested another imperial messenger.
He therefore sent another official, Zhang Zhuo (張著), to Shannan East, honoring Liang with the honorary title as chancellor, creating his wife as a lady, bestowing on him an iron certificate (guaranteeing that he would not be put to death), and summoning him to Chang'an.
He also accepted Liang's prior recommendation that one of the officers he favored, Lin Gao (藺杲), be made the prefect of Deng Prefecture (鄧州, in modern Nanyang).
In reaction, Emperor Dezong created Li Xilie the Prince of Nanping and put in him charge of the operations against Liang.