1. Goguryeo has always been regarded as an integral part of the Central Plains regime
As early as the Shang and Zhou dynasties, the Central Plains regime had already established some kind of connection with the regime on the Korean Peninsula. As early as the Shang Dynasty,King Shang's uncle, Keiko, fled to the northeast and established the Mizi Joseon on the Korean Peninsula. After the establishment of the Zhou Dynasty, the Jizi Joseon Dynasty also chose to bow down to Zhou Tianzi and accept its canonization.
Until the end of the Warring States period, Jizi Korea was destroyed by the Yan people Wei Man, and the regime in the Korean Peninsula region was also transformed into Wei KoreaBut in the end, it ushered in the fate of being wiped out during the reign of Emperor Wu of the Han Dynasty. On the basis of the original Wei Korean territory, Emperor Wu of the Han Dynasty established four counties of Lelang, Lintun, Xuansu and Zhenfan in the local area, and the Korean Peninsula was also included in the direct jurisdiction of the Western Han Dynasty.
During the troubled period of the Wei, Jin, Southern and Northern Dynasties, the Central Plains regime was neither able nor willing to spend energy on the Korean PeninsulaThis provided an opportunity for the establishment and development of the Goguryeo regime, and gradually developed independent ambitions.
Even so, Goguryeo still had close ties with the Central Plains regime, ostensibly accepting canonizations from the Central Plains regime and sending envoys to pay tribute, a situation that remained unchanged until the establishment of the Sui Dynasty.
It was precisely because of this long-standing close connection between the Korean Peninsula region and the Central Plains regime that the Sui Dynasty also gained a kind of moral support in its conquest of Goguryeo.
After all, under the influence of the ideology of "the whole world is not the king's land", the ancient rulers paid more attention to internal unity and stability. And Goguryeo, as a regime that was absolutely subordinate to the Sui Dynasty in terms of culture and warfare, was naturally the primary target of this kind of internal unification and stability.
2. Goguryeo itself posed a threat to the Sui Dynasty border at that time
For the Sui Dynasty, the greatest enemy was the Chen Dynasty in the south. However, in this situation of confrontation between the north and the south and the imminent outbreak of war, Goguryeo fully demonstrated its swaying style of wall-to-wall grass.
At that time, while accepting the title of Liaodong County of the Sui Dynasty and sending envoys to attack the Sui Dynasty from time to time, Goguryeo secretly maintained contact with the Chen Dynasty in the south, which obviously touched the political bottom line of the Sui Dynasty.
In addition, from before the establishment of the Sui Dynasty to after the fall of the Sui Dynasty, the Turkic forces in the north were always the henchmen of the Central Plains Dynasty. However, Goguryeo secretly contacted various minority regimes, including the Turks, and Emperor Yang of Sui even bumped into Goguryeo's envoy at a meeting with the Turkic Qimin Khan.
It can be seen from thisWhile superficially subjugating the Sui Dynasty, Goguryeo always tried to form a diplomatic system of distant friendship and close attack to exert sufficient military pressure on itIn order to create opportunities for their own expansion in the Liaodong region, this was of course also shameful and vigilant for the Sui Dynasty.
3. Goguryeo's military expansion affected the actual interests of the Sui Dynasty
Since the end of the Eastern Han Dynasty, as the Eastern Han regime gradually weakened, its control over the four counties of Liaodong was much weaker, which provided an opportunity for the local population of the Korean Peninsula to expand their power.
After that, with the advent of the turbulent era of the Wei, Jin, Southern and Northern Dynasties, the actual control of the Central Plains regime over the Korean Peninsula fell into an extremely declining state.
These things all happened before the Sui Dynasty established and completed the great cause of unification, and the Sui Dynasty did not pursue it too much. However, after Goguryeo submitted to the Sui Dynasty, it still infringed on the interests of the Sui Dynasty from time to time in specific military operations, which was obviously not tolerated by the latter.
At that time, in the headquarters of the Korean Peninsula, Goguryeo always tried to complete the invasion and occupation of the Baekje regime in the south in order to achieve true reunification of the Korean Peninsula region.
But,Baekje itself was part of the Sui Dynasty's vassal system and had the same status hierarchy as Goguryeo, and the latter's invasion of the former was undoubtedly a great offense to the Sui Dynasty.
Therefore,When Goguryeo invaded Baekje, Emperor Wen of Sui issued an edict that "(Baekje) is afraid of submission and blame, and I have pardoned it, and it cannot be killed." However, Goryeo still insisted on sending troops. Whether it was out of their own practical interests or to maintain their own status, the Sui Dynasty needed to punish Goguryeo to a certain extent.
In addition, in the tributary system, the Sui Dynasty was the sole hegemon in East Asia, and the other local ethnic regimes were in an equal position of domination.
However, at that time, Goguryeo tried to rely on strong force to establish a tributary system that was independent of the Sui Dynasty and dominated by itself.
As for the Khitan tribes, Goguryeo also adopted a variety of coercion and temptation methods to win over some of them and submit to them. In such a case,The Sui Dynasty could no longer tolerate it, and brazenly launched a war against Goguryeo, in which the number of troops was even as high as one million, which is enough to show that the rulers of the Sui Dynasty attached great importance to the threat posed by Goguryeo. It's just that in the end, the outcome of the war was unsatisfactory and ended with the repeated defeats of the Sui Dynasty.
4. The conquest of Goguryeo hastened the demise of the Sui Dynasty itself
As early as the time of Emperor Wen of Sui, the Sui Dynasty had already shown a trend of partial decline. For example, the internal officials are corrupt and the program is often chaotic. However, after succeeding to the throne, Emperor Yang of Sui not only did not set things right, but instead devoted himself to establishing his own merits.
Driven by ambition, Emperor Yang of the Sui Dynasty built the Grand Canal in the south of the Yangtze River, which greatly consumed domestic human, material and financial resources.
But it was in this situation that Emperor Yang of Sui requisitioned the whole country to attack Goguryeo, and finally suffered a huge defeat, which made the already withered society even worseThe people could not bear it anymore and broke out a war against the rule of the Sui Dynasty, which sounded the death knell of the Sui Dynasty.
For the Sui Dynasty and other Central Plains dynasties, Goguryeo was not just a local power, but an internal vassal state with close political ties and cultural customs.
Therefore,Even if some of the Central Plains Dynasty were unable to achieve actual control over Goguryeo due to strength limitations, once they had the opportunity, the Central Plains Dynasty would never tolerate any disobedience to GoguryeoThis was the case with the Sui Dynasty, and the subsequent Tang Dynasty still insisted on deciding to crusade against Goguryeo after the defeat of the Sui Dynasty, which is also a manifestation of this mentality.
However, what is unexpected is that the Sui Dynasty suffered a complete defeat in the struggle against Goguryeo, not only failed to maintain its dignity and status, but accelerated its own demise.