During the Goguryeo–Tang War, the siege of Anshi represented a critical military engagement between the forces of the Tang Dynasty, led by General Li Shiji, and the Goguryeo kingdom. At that time, Anshi, situated in present-day Liaoning, served as a vital fortress owing to its strategic location that provided a gateway to control northeastern territories. The siege was part of the Tang's broader efforts to assert dominance over Goguryeo, which had maintained its autonomy amidst the expansionist desires of the Tang Dynasty following the fall of the Sui Dynasty.

Li Shiji was known for his military prowess and strategic acumen, attributes he showcased during the protracted siege. Utilizing siege warfare tactics, innovative strategies, and the logistical strength of the Tang forces, Li aimed to capture Anshi to weaken Goguryeo’s eastern defenses. The siege involved not only direct assaults on the fortifications but also psychological tactics to demoralize the enemy defenders. As the siege dragged on, supply lines for the besieged forces became a critical focus, illustrating the importance of such logistical aspects in military confrontations.

Despite the siege’s intensity and initial successes, captured fortresses did not immediately translate into a decisive victory for the Tang. The resistance from Goguryeo was fierce, showcasing their resolve and resourcefulness in defending their homelands. The extended nature of the siege highlighted the challenges faced by Tang generals in the difficult terrain and against a motivated foe. Ultimately, the siege of Anshi was emblematic of the larger ongoing conflict that defined Sino-Korean relations during the Tang era, reflecting the era's complexity and the ambitions of the Tang Dynasty in Northeast Asia.