Writing an historical research paper can be stressful. It can be worse when the instructor requires you to choose the topic and create your own thesis statement. But not any topic will be acceptable.
Let us say that you are taking a class on Ancient Greece. Just to write a paper on the history of Athens will not bring an A to the paper. This is a research paper that you are writing. A paper on the history of Athens is just a restatement of history. A research paper does much more than that.
As you choose a topic, you need to take the hat of academic off and replace it with the hat of a detective. A research paper is to explore a topic from a new angle and give it credible support. So, how do you choose an historical research paper topic? Look closely at the list your instructor provides you or at your textbook.
Start with what interests you. There are some topics that we quickly shy away from. There are some topics that we want to know more about. Strike off those that you dislike or are not comfortable with. See what is left on the list of possibilities. You could still have twenty or thirty possibilities. Now, you need to eliminate a few more.
Go down your list. Can you think of a theory on the first topic that you have and would love to research and prove? For example, maybe you firmly believe that the Greco-Persian wars were as long as they were due to Spartans inactivity in the beginning of the wars. Maybe you feel that the Spartans were the main ones responsible for the Peloponnesian War because of their unwillingness to be a part of the rest of Greece. Maybe you have a different take on the Battle of Thermopylae that no one has really looked at.
If you cannot think of something that you could propose and argue substantially with credible support, then strike that topic and move on. You might have five topics left. You need to get down to one. If you just cannot choose between the choices in front of you, now is the time to begin looking at the number of resources on the subject. If you cannot find more than two or three resources to put in your bibliography, then that topic should be struck even if you really like it. You want to have at least seven good sources available to you.
Remember that a research paper is not a regurgitation of facts. It is an exploration of an historical topic. It is you proving a theory.