Heaven's Will

Thuận Thiên (, Heaven's Will) was the mythical sword of the Vietnamese King Lê Lợi, who liberated Vietnam from Ming occupation after ten years of fighting from 1418 until 1428. Lê Lợi then proclaimed himself king of the newly established Lê Dynasty. According to legend, the sword possessed magical power, which supposedly made Lê Lợi grow very tall. When he used the sword it gave him the strength of a thousand men, and the legend is often used to justify Lê Lợi's rule over Vietnam. The sword has been associated with Lê Lợi since the early phase of the Lê Dynasty.

The Thuận Thiên sword was used to affirm the legitimacy of Lê Lợi as the Vietnamese leader in the revolution against the Ming occupation and associated with Lê Lợi the rightful sovereignty of Vietnam. In Vietnam, the legitimacy of the monarch is known as the mandate of heaven.

Lê Lợi revolted in 1418 against the Ming Dynasty, who had invaded and occupied Vietnam in 1407. Initially the military campaign against the Chinese was only moderately successful. While Lê Lợi was able to operate in his home province of Thanh Hóa, for the first 2–3 years, he was unable to muster the military forces required to defeat the Ming army in battle. As a result, he waged a guerrilla campaign against the large and well organized Chinese army. According to legend, to help Lê Lợi, a local God, the Dragon King (Vietnamese: Long Vương) decided to lend his sword to Lê Lợi. But there was a catch; the sword did not come straight to him in one piece. It was split into two parts: a blade and a sword hilt.

First, in Thanh Hóa province, there was a fisherman named Lê Thận, who was not related to Lê Lợi in any way. One night, his fishing net caught something heavy. Thinking of how much money he would get for this big fish, he became very excited. However, his excitement soon turned into disappointment when he saw that his catch was a long, thin piece of metal which had somehow become entangled to the net. He threw it back into the water, and recast the net at a different location. When he pulled the net in, the metal piece had found its way back into the net. He picked it up and threw it far away with all its strength. The third time the fishing net came up, the same thing happened, the metal piece was once again caught in the net. Bewildered, he brought his lamp closer and carefully examined the strange object. Only then did he notice that it was the missing blade of a sword. He took the blade home and not knowing what to do with it, put it in the corner of his house.

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Wikipedia