Is there Xue Dingshan in history?

There is no Xue Dingshan in history, but there is his prototype.

Xue Dingshan (649-720 AD) is a character in the novel Romance, and his historical prototype is Xue Ne, the son of the famous Tang Dynasty scholar Xue.

Xue Dingshan's mother is Liu Jinhua. He married Fan Lihua, Dou Xiantong and Chen Jin successively, and once led the army to pacify Xiliang (West Turkic). Later, because his son Xue Gang was drunk and killed by midnight snack, Emperor Gaozong was ordered to be executed by Wu Zetian.

Extended data:

Xue Ne, be careful, it's Xue's son. When he was the magistrate of Lantian county, he dared to refuse the unjust behavior of the cruel officials of the dynasty.

Later, when the Turks invaded the frontier, Wu Zetian transferred Xue Ne to the front line of Youzhou because he was behind the door. Xue Ne has been stationed at the border for a long time and has made great achievements. Xuanzong once practiced Tang Jun in Xinfeng, but only Xue Ne's reconciliation department advanced and retreated in an orderly way.

Turks, Khitan and Xi jointly invaded the frontier, and Xue Ne strongly advocated the attack, with the permission of Emperor Xuanzong of the Tang Dynasty. However, due to the obstruction of other generals, Tang Jun was defeated and Xue Ne was dismissed.

Soon, the Tubo army invaded the border with 100,000 troops, and Xue Ne was reopened as our envoy in Longyou. He defeated Tubo in succession at Wu Jie Post Station and Great Wall Castle, and seized numerous checkpoints. Xue Ne has been guarding Xiliang since then and died at the age of 72.

Xue Ne in history really reached the peak of his career in Xiliang.

References:

Xue Dingshan? Baidu baike