Why do so many people have the same last name if they aren't related?

Question:

Why do so many people have the same last name if they aren't related?

Best Answer - Chosen by Asker: I would assume that you are referring to people in the United States. With this being the case, let me try to answer your question.

The use of a last name or surname is a comparatively recent phenomenon. Surnames were adopted in order to legally distinguish two individuals with the same given name. Different areas of the world adopted surnames at different periods in time. For example, surnames were commonly used two thousand years ago in areas occupied or influenced by the Romans. Other areas of the world were slower to begin using surnames, but they were coming into regular use by the time of the Middle Ages, first by the nobility, then by the gentry. After the fall of the Roman Empire, Ireland was one of the first countries to adopt hereditary surnames, and Irish surnames are found as early as the tenth century.

Surnames are generally derived from one of four sources: the name of the person's father, the person's locality, the person's occupation, or a descriptive nickname for the person. When they were created, they answered one of the following questions: Who is this person's father? Where is this person from? What does this person do for a living? What is his or her most prominent feature?

This is why there are so many Smiths and Johnsons for example. Even though they are not related there were a lot of blacksmiths and sons of John. In the early years of surnames, the surname wasn't passed on from father to children, but each child was given a different surname based on one of the items above. I hope this helps answer your question.