Jim Crow
Created by Thomas D. Rice, Jim Crow is a character that would used in performances that often involved blackface. This stage persona would lead its name for negative stereotypes of black people. Many of us have heard of “Jim Crow” segregation laws that were in effect until the Civil Rights act was signed by Lyndon Johnson. However, Jim Crow was not an actual real person.
John Doe and Jane Doe
You might have heard of the names John and Jane Doe, as these are used to name people whose real names are unknown or being concealed. There was never an actual John Doe historically but it was used because it satisfied technical requirements of jurisdiction. The rationale behind these names are not known.