辽东或称辽左、辽海,泛指今辽河流域及其以东广大地区。自战国燕置辽东郡始,辽东地区一直处于中原王朝的直接管辖之下,成为其领土重要组成部分。5世纪初,前汉末年兴起于浑江中下游一带的高句丽逐渐强大,趁中原王朝衰弱之机,逐渐占有辽东地区。在汉代郡县区域内发展起来的高句丽,在魏晋南北朝时期,一直和南北方的中原王朝保持着密切的关系。在政治上,接受中原王朝的封号,为其藩附;在经济上,向中原王朝纳贡。隋朝建立后,用兵东北,意在收复高句丽地方割据政权统治下的辽东。隋朝灭亡后,唐朝初年继续用兵辽东。这是隋唐统 Liaodong, or Liao left, Liaohai, refers to the Liaohe River Basin and the vast east of the region. Since the beginning of the Warring States Period, Liaodong County was set up. The Liaodong area has been under the direct jurisdiction of the Central Plains dynasty and has become an important part of its territory. At the beginning of the 5th century, Goguryeo, which grew up in the middle and lower reaches of the Hunjiang River at the end of the former Han Dynasty, became stronger and stronger. While taking advantage of the weakening of the Central Plains dynasty, it gradually occupied the Liaodong area. During the period of Wei, Jin, Southern and Northern Dynasties, Goguryeo developed in the Han dynasty counties and counties maintained a close relationship with the Central and Southern Dynasties Dynasty. Politically, accept the title of the Central Plains dynasty, attached to its feudal clan; economically, tribute to the Central Plains dynasty. After the establishment of the Sui Dynasty, the troops northeast, intended to regain the Goguryeo local regime under the rule of the Liaodong. After the demise of the Sui Dynasty, the early Tang Dynasty troops continue to use Liaodong. This is the Sui and Tang dynasties