Benjamin is a Hebrew name meaning "Son of the right hand". If your family tree has a Benjamin it could be that your ancestors had an affinity for the ancient Israelites. Used alone, Ben means "Son of". You will find the Hebrew prefix Ben, used abundantly in Hebrew names as in Ben Jacobs, of course meaning "Son of Jacob". It makes it hard to trace our ancestors when their ethnicity and or religion changed from Hebrew to Hebrew- Christian and eventually to Christian, but knowing the origins of both first names and surnames is a great place to start.
Suellen Ocean is the author of Secret Genealogy a how-to for tracing ancient Jewish ancestry and Secret Genealogy II, Uncovering the Jewish Roots of Our Christian Ancestors, both available at Amazon, B&N and Ocean-Hose. http://www.pacificsites.com/~oceanhose/