Xu Gai, the son of Xu Huang, a famous general of Cao Wei during the Three Kingdoms period, was born in Yang County, Hedong County. When Xu Gai was born, it was when the imperial court named Xu Huang as Yang Hou, and it was also a great honor for the Xu family to be sealed in his hometown. When Xu Gai grew up, his personality was the same as that of his father Xu Huang, who was cautious and frugal. However, unlike his father, Xu Gai developed a strong interest in Buddhism from an early age, but he was not interested in martial arts, so despite being born into a family of military generals, his martial arts achievements were not high.
In 226, Xu Huang was seriously ill, and Xu Gai suggested that the family fund the construction of a big Buddha to pray for his father, so his grandmother Wang funded the construction of a big Buddha in the land of Qilu. Xu Gai and his grandmother, Wang, hoped to alleviate his pain by praying for blessings, and even hoped for a miracle.
Wang took Xu Gai into the temple and prayed to the Buddha sincerely. Tears flowed down, and she said in a trembling voice: "Buddha, please bless my son Xu Huang and let him recover as soon as possible." Xu Gai also burst into tears, and he continued: "My father is a hero in my heart, he taught me to be brave, upright, and prudent, and I am willing to use all my strength to protect him." Buddha, please help my father through this difficult time. They knelt together in front of the Buddha statue, clasped their hands together, and prayed silently. At that moment, the sound of their prayers spread throughout the temple, as if echoing the Buddha's compassion. No matter what the outcome is, their prayers are a sincere emotion and reverence for life.
Later generations in the west wall of the Big Buddha Grottoes, found a statue inscription, which was engraved: "Like the main Rong monk Yu (the square word is the dagger on the right), like the main Luo Shengnan, like the main Gao Qiu Wang, like the main Xu Huang's mother, like the director (next to the single person is also Zhi) Jinghui." This inscription not only confirms the authenticity of Wang's funding for the construction of the Buddha, but also gives us a glimpse of the people of that era, their faith, their kindness, and their lives.
In 227, although Xu Gai and his mother Wang prayed for Xu Huang, Xu Huang eventually died of illness. Xu Huang was known for his bravery during his lifetime, and when he was dying, he left a testament requiring his funeral to be simple and to be buried in clothes.
After Xu Huang's death, in recognition of his merits, the imperial court posthumously gave him the nickname "Marquis of Zhuang", and at the same time, the imperial court let Xu Gai inherit Xu Huang's title of Marquis of Yangping (Xu Huang changed from Marquis Yang to Marquis of Yangping). Yangping County was once the place where Xu Huang guarded, and Xu Gai inherited not only his father's title, but also his father's glory.
After Xu Gai inherited the title, he continued to maintain the honor of the family, but there are not many other records about him. After Xu Gai's death, his son Xu Ba succeeded him to the title. With the establishment of the Western Jin Dynasty, the feudal system was abolished, and the title of the Xu family came to an end.