The history of Li Shimin’s three major Goguryeo symbols

Introduction: Li Shimin, the second emperor of the Tang Dynasty, regarded Liaodong, where Goguryeo belonged, as "the existence of old China". Now, in the "only corner", he was determined to conquer Goguryeo as the last step in the war of unification of China. Tang Zizhen observed Zhen's life for four years. Gaochang was destroyed in fourteen years. Yanqi was destroyed in the eighteenth year; he invaded South Korea for the first time. Xue Yantuo was destroyed in twenty years. In the 21st year, he conquered Korea and killed Qiuci. In the 22nd year, he conquered Korea three times. Emperor Taizong died in the 23rd year of the Tang Dynasty. After the defeat of Goguryeo in the Sui Dynasty, a civil uprising occurred in the country and the country was destroyed. Goguryeo remained hostile to the Tang Dynasty, which later became the Chinese dynasty. In 61 AD, in order to prevent the Tang Dynasty from attacking, Goguryeo began to build the Great Wall in Liaodong and formed an alliance with the Turks. The Second Emperor of the Tang Dynasty regarded the "Liaodong" owned by Goguryeo as "the existence of old China". Now it was a "one-man show" and determined to conquer Goguryeo as the last step in the war of unification of China. However, the Tang's attack on Goguryeo was not successful at first. After defeating Goguryeo's allies, the Turks, Tang formed an alliance with Silla. In 62 years, Su Wen, the beggar of the Yuan Dynasty, killed Goguryeo. The left king Gao Jianwu and the king Gaoma Debao proclaimed themselves the regents of Mori. In order to protect Silla, an ally of the Tang Dynasty, Tang Taizong deemed it necessary to go to war with Goguryeo. In 64 years, Emperor Taizong of the Tang Dynasty took Li Shiji, Li Daozong, Sun Changwuji and his 100,000 troops to personally visit Goguryeo. In 65 years, Emperor Taizong of the Tang Dynasty broke through the Goguryeo defense line and prepared to attack Pyongyang. It seemed his success was imminent. Unexpectedly, he was blocked in Anshi and could no longer move forward. Due to the severe winter weather and Xue Yantuo's invasion of the Tang Dynasty, the Tang army was forced to return. After that, Tang Taizong's attack on Goguryeo only maintained some small-scale raids. In 66 AD, King Bao gave two beauties to Emperor Taizong of the Tang Dynasty as a token of goodwill, but Emperor Taizong did not accept them. Emperor Taizong of the Tang Dynasty gave Gai Suwen a bow and robe, and Gai Suwen accepted it, but no one sent an envoy to thank him, so Emperor Taizong of the Tang Dynasty issued an edict to cut off tribute. In 647, after Tang Huihe and other Tiele clans destroyed Xue Yantuo, Tang Taizong ordered Niu Jinda to lead troops from the sea and Li Shiji to attack the Liaodong Peninsula from the land. In 68 AD, Emperor Taizong of the Tang Dynasty sent Xue Wanche to attack the mouth of the Yalu River from the sea. Later, in 649, Tang began to mobilize the army and navy to attack Goguryeo on a large scale again. According to the "Old Book of Tang", Tang Taizong had been running a navy before launching a large-scale attack on Goguryeo in 649. The First Eastern Expedition: Started in July of the 18th year of Zhenguan, attacked Anshi in September, and returned to the army. The Second Crusade: This Crusade was divided into two wars: the 21st year of Zhenguan, the land march in March, and the retreat to the west of Pyongyang in July. In the first month of the twenty-second year, they marched by water, and in April they marched north to Yizhou and Pyongyang. The Third Eastern Expedition: In June 22, preparations were made for a large-scale expedition to Korea and naval forces. In May of the following year, Tang Taizong died and the Eastern Expedition was launched. The First Crusade The Second Crusade 1. The Tang Dynasty Battlefield The geographical situation of Korea, its northwest frontier is bounded by Liao and Tang. It faces the sea to the west and is as far away as Laizhou in the Tang Dynasty. Its northeastern part is the Mill Creek part. It borders the sea to the east and Silla and Baekje to the south. There were three dangerous areas in the Tang Dynasty of Korea: Liaoshui area: In the fifth year of Zhenguan, Wang Jianwu of Korea built the Great Wall from Fuyu City along the east bank of Liaoshui River to the southwest "a thousand miles" into the sea for fear of invasion by the Tang Dynasty. Between the Yalu River and Qianshan: Maruyama Capital

Judging from the conditions of the cities listed above, there are three routes to attack the North Korean capital Pyongyang from Liaodong: from Liaodong to Lianshanguan in the Qianshan Mountains, and via Fengcheng This is the main road to Hamhung County, and it is also the road for North Korean tribute. It is the west road from Gaimou Beisha City to Yizhou via Fuyu City. From Gentu to the Thousand Mountains to Marudo. This was the only way for the Korean army in the Tang Dynasty. The Tang Navy also had two ways of attacking North Korea: starting from Laizhou, passing through Daxie Island, Wuhu Island and other Northeastern islands, then crossing the Wuhu Sea, and then from present-day Lushun and Dalian or east to the mouth of the Yalu River to Pyongyang, or north to the Liaohe River The mouth cooperates with the army to fight. From Chengshan, cross the Yellow Sea to Pingyang and the mouth of Jinxiong River to attack Baekje. two. Tactics of both sides of the Tang Dynasty: After the Gesuwen coup, North Korea was in a state of turmoil with Baekje in the north and Japan in the south. The West had implicit resistance to the Tang Dynasty, which was the main ally in the East. After Emperor Taizong of the Tang Dynasty destroyed the East Turkistan, he had a plan to lead the entire Asian alliance, so he refused the order of the Beggar Gang and became an attacker. The base area for Tang Taizong's expedition to Korea was the same as that of the Sui Dynasty. It used Youzhou and Yingzhou as the source of the army, and Laizhou as the source of the navy. Food was also collected from Wuhu Island to supply the Eastern Expeditionary Army. At the same time, in view of the failure of the Sui Dynasty's conquest of Korea, Tang Taizong took the following important measures: strict deployment and control in important strategic places in China's rear, such as the capital Chang'an, the eastern capital Luoyang, Dingzhou and other places, to prevent unrest in the rear. Recruit the bravest volunteers from all over the world to form a new army and avoid local unrest caused by forced conscription. The water and land forces cooperated closely, so the general's main force was directed at Yu'an City. Adopt a policy of releasing prisoners in large numbers and giving priority to prisoners in order to undermine North Korea's morale and popular support. After attacking Anshi for a long time, he retreated. Knowing that Goryeo was good at defending the city, he divided his troops to disrupt the war situation and wait for the disadvantages. A large number of ships were built in the Jianghuai River to expand the naval force so that the Tang army could attack Pyongyang. Gaozong still inherited Tang Taizong's strategy and continued to adopt the policy of disintegrating operations and expanding the navy, but was eventually defeated by his civil strife. Goryeo: First, it still followed the tactics of the Sui Dynasty's defeat, using three overlapping defense lines, using city defense tactics and weather advantages to delay the Tang army's invasion. After the Tang army fought for a long time, the food ran out, the soldiers were exhausted, and the weather changed, and then they launched a counterattack against the Tang army.