In 53 BC, crassus, one of the three giants of the Roman Empire, led the first Roman legion to attack the kingdom of Parthia in Central Asia (called the rest country in China history books, located on the Iranian plateau). The Parthians fought to the death. In May, the Roman Expeditionary Force entered a place called Calais and was ambushed by Parthians. Facing the dark Parthian army, crassus, unwilling to lay down and die, made a desperate breakthrough. After a fierce battle, the Roman legion completely collapsed, and crassus ordered his men to escape. After the Battle of Calais, the Roman Empire temporarily stopped harassing Parthia. In 20 BC, the two countries made peace. However, when the Romans proposed to repatriate all Roman soldiers captured in the Battle of Calais, there was one thing that puzzled them. When counting the number of prisoners of war, they found that there were only a few hundred. However, the news they got before was that many soldiers of the First Legion did not actually die, and the Romans and Parthians were in a state of confusion for some time.

Later, historians finally solved the mystery. It turned out that more than 1000 Roman soldiers rushed out of the encirclement. If they want to survive, their only choice is to avoid the blockade of Parthia's army and continue eastward. Finally, the remnants of the first Roman legion rushed out of the Parthian border and entered the Central Asian basin. There, however, are scattered small countries like Kangju and Da Yue. As a result, Roman soldiers who were good at fighting were accepted as mercenaries by these small countries. After these Roman soldiers came to Central Asia, they still maintained an independent fighting and lifestyle. If there is no big change, they are likely to gradually multiply and take root here. However, at this time, a war changed their fate again. The special prisoners of the Han army were Roman soldiers who fled to Central Asia that year. Some of them went to Kangzhou, while others acted as mercenaries in Da Yue. In 40 BC, Da Yue's family was in turmoil, and Wang Zhiyi, the assistant general, started a war and became the king of Da Yue. The defeated four kings fled eastward to the Hexi Corridor of the Western Han Dynasty with their own troops and subjects, including those Roman soldiers. There, these Roman soldiers were properly placed. Roman soldiers who fled to Kangju were not so lucky, because they were involved in the war between the northern Xiongnu and the Western Han army.

Since Emperor Wu of the Han Dynasty, the Xiongnu in the western Han border suffered many blows. In 57 BC, there was a coexistence of five orders in the Xiongnu. In 53 BC, Uhaanyehe declared that he belonged to the Western Han Dynasty, and led his troops to move south to the vicinity of Yinshan Mountain. However, Zhi Zhi Khan, an enemy of the Western Han Dynasty, was afraid of calling on the evil spirits of the Han Dynasty to unite with the Han army to attack him, so he led his people to the west of Central Asia. In 40 BC, when Khan's army arrived in Kangzhou, there were only more than 3,000 people left. However, Zhi Zhi Khan soon got help from Kangju. King Kangju not only placed Zhikhan on the eastern border, but also lent him his Roman soldiers. In this way, the remaining Roman legions once again became mercenaries of the northern Xiongnu army.

With the help of Kangju, Zhi Zhi Khan soon became strong again, and insulted the western countries, and also built Zhi Zhi City, ready to compete with the Han army. In 36 BC, the Western Han Dynasty sent troops to crusade against Zhiyu, because the activities of Zhiyu seriously threatened the security of the countries in the western regions of the Han Dynasty. When the Han army surrounded Zhi Zhi, they found these strange soldiers in the other army. According to China's historical records, Zhi Zhi City is not only guarded by a "heavy wooden city outside the Tucheng", but also a "hundred infantry fish scale array". According to the previous understanding of Han people, it is impossible for Huns, as nomadic people, to master these tactics. What is even more surprising is that during the battle, these soldiers held high a huge shield one person high. They formed a square queue, wrapped the team tightly with the shield, and then shouted slogans and marched in a unified pace. When the enemy is far away, throw the spear out first; Come a little closer, and then pull out the knife and fight. However, due to the gap in strength, this strange tactic did not change the outcome of the battle. Due to the high speed of heavy cavalry in Han dynasty, the phalanx of Roman soldiers was surrounded instantly, and then attacked from all sides, easily breaking through the phalanx of Roman soldiers. Finally, the Han army broke through Zhi Zhi City in one fell swoop. And those poor Roman soldiers, only 100 people left, became the prisoners of the Han army.

The Han army brought these Roman soldiers back to China. In order to resettle these special prisoners, Emperor Hanyuan specially issued a letter to establish Li Gan County (now Yongchang County, Gansu Province) in Hexi area. According to the Book of the Later Han Dynasty, "Li Gan County was established in the early Han Dynasty, and the county was named after the country", and some historians in later generations also thought that Li Gan was the name of the Roman Empire in the Han Dynasty. Since then, the descendants of the once-missing Roman First Legion have thrived here. Until 592 AD, Emperor Wendi of Sui Dynasty merged Li Gan County into Fanhe County. Since then, there is no record of these Roman soldiers in China's history books. Note: Regarding this period of history, some scholars have verified that Ma Chao's Xiliang Army is descended from Rome, and the authenticity is unknown. It is worth mentioning that the Han Dynasty never confronted the Roman Empire head-on, but dealt a heavy blow to the northern Xiongnu, forcing the Xiongnu to move westward, and it was these fleeing Xiongnu who destroyed the divided Roman Empire. It is said that the descendants of ancient Rome are still handed down to this day, and many people in the villages around Li Gancheng (Yongchang County, Gansu Province) still have typical Mediterranean characteristics.

I was very interested in this topic, so I looked up some information. Although it is plagiarized, I hope you can understand it.