[somenomadicguy]

Immigrant officials at Ellis Island used to give people last names based on their father's first name, or the name of the city they come from.

Also, Armenians didn't have last names until recently, so you'll meet lots of people with names like "Gevork Gevorkian" or "Ohan Ohanesian", or their name will be shifted to the right, adding an "ian" to the end (think the prefixed O' in irish names), and give them anglicized names.