The Vietnamese began using last names in about 111 B.C., when China conquered Vietnam. China has uses last names for thousands of years. When during their 1,000-year occupation of Vietnam, they assigned last names to groups of people to make tax collection more efficient.
The most popular last name in Vietnam is Nguyen, which was the name of the ruling dynasty from 1802 to 1945. The people of Vietnam weren't all that attached to last names, and would frequently change them to that of the ruling family. About 40 percent of Vietnam's population is named Nguyen.
Most Popular Vietnamese Last Names on FamilyEducation: Nguyen, Tran, Le
Image: Floating Village in Halong Bay, Vietnam