Why did 1979 call Vietnam, and 1985 called again?

Because 1979 fought Vietnam, it was called the self-defense counterattack against Vietnam (the self-defense counterattack on the border between China and Vietnam), and 1985 recaptured Yinshan, which triggered the "two-mountain round battle".

Vietnam is a neighboring country to the south of China. As a county in China, Vietnam has always belonged to the administrative division of China. At the end of the Five Dynasties and Ten Kingdoms, the Ding Dynasty in Vietnam became independent from Nanhan in China. After the failure of recovering Annan in the Song Dynasty, Vietnam officially became an independent vassal state recognized by the China government.

1979, the China people's liberation army counterattacked Vietnam in self-defense, pushing the east-west front 30-50 km to the north of Vietnam, reaching 100 km as far as possible. Recovered the territory of Punianling and Tinghao Mountain in China occupied by the Vietnamese army; Capture the three provincial capitals of Gaoping, lang son, Huanglianshan and Laizhou in northern Vietnam.

Extended data:

A Review of the "Two Mountains Round" War

China's self-defense counterattack against Vietnam is divided into two stages: the first stage is the self-defense counterattack, that is, the Battle of 1979, which formed a situation of bullying Hanoi. In the later stage of Vietnam's counterattack, the confrontation between China's army and Vietnam's army was carried out in Laoshan, Yinzheshan and Faka Mountain.

It took a long time in the later period, and it basically stopped at 1989. Starting from 1984, China's army concentrated on uprooting several strongholds, such as Laoshan and Shading Mountain, which were controlled by the Vietnamese army, and transferred the troops of various military regions to fight from 1984 to 1989. This is the "two-mountain round war."

Baidu Encyclopedia-Round Battle of Two Mountains

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