When writing an essay, should I only cite paraphrased or quoted information in my bibliography?

If I use something for background info., do I have to cite it.

2 answers

Yes.
Quoted information MUST be cited.
Paraphrased statements should also be cited. "John Doe (1999) contends that George Washington was a traitor." Whether it's "background" or any other purpose. Your own thesis and summary, your own interpretations, are not cited, since there is no citation.