History is studied through indirect measurements - written accounts, archaeology, oral history. All reasonable scientific routes. As allowed by the OP?
But that is different to the "observe", "measure", rinse-and-repeat methodology which is commonly understood as the scientific method.
The methods by which one studies physics and history are different, but history is no less scientific, and it falls within the sciences, as does theology since it depends on the historical method.
Theology cannot argue or learn anything about God for which there is no historical basis.
