It's called a "nom de plume" or pen name. It goes back centuries. Usually it's for anonymity, but the name also is used as a reference for the reader. For example, the Federalist Papers (which argued for ratification of the Constitution) were pen-named as written by "Publius" and ancient Roman known for his rationality, when they were written by Alexander Hamilton, Madison, and John Jay.

Likewise, many of the Anti-Federalist papers were written by "Brutus" who assassinated Caesar, an obvious reference to a fear of the central government that would come from the Constitution.

It's called a "nom de plume" or pen name. It goes back centuries. Usually it's for anonymity, but the name also is used as a reference for the reader. For example, the Federalist Papers (which argued for ratification of the Constitution) were pen-named as written by "Publius" and ancient Roman known for his rationality, when they were written by Alexander Hamilton, Madison, and John Jay.

Likewise, the many of the Anti-Federalist papers were written by "Brutus" who assassinated Caesar, an obvious reference to a fear of the central government that would come from the Constitution.