Well, as I understand it - and there may be others here better qualified to comment on the nature of history as a discipline - it's a mixture. Some of of it certainly is to do with ascertaining the truth of events in the past, but it is also concerned with how people saw events and processes from various points of view. This Britannica article goes into it a bit:
Philosophy of history | Summary, Theories, Philosophers, & Facts
How people saw events, all that makes up a subjective actor in historical events, is an objective occurrence. If the historian is putting words in the mouths of historical actors or assigning beliefs and attitudes to historical actors that they did not hold, then yes, that would be fiction and not empirical. If on the other hand, the historian strives to capture and represent with fidelity the words of the historical actor and through that build a picture of that actor's beliefs and intents, and especially evaluating those words within the cultural context in which they were spoken, then I would see that as an empirical activity. Of course, we *are* dealing with the behaviors and actions of human beings. Human beings who are not completely open books and beyond being guarded and deceptive in their external interactions also have the capacity for self-deception.
Does all this make the historians job all the more difficult? Of course. Does it mean historians should give up and not strive for fidelity and accuracy? Absolutely not, in my opinion. It just means that their conclusions can only be asserted and received as falling within some range of confidence.
I'm not convinced the latter really qualifies as empirical, unless one takes that to encompass any academic field in which one reads, considers and draws conclusions from what others have written. And if one does that, then theology is also an empirical study, isn't it?
First, let me say that science *is* philosophy. What distinguishes this improvement in philosophy, born out of work in natural philosophy, is the fundamental acknowledgement and acceptance that human beings are inherently imperfect and fallible. It was the sobering realization that the philosopher could not trust themselves implicitly to be free from error, a realization that the philosopher could no longer rely on their intelligence or cleverness alone. Intuition could no longer be regarded as infallible. It means that the philosopher must maintain a posture of rational skepticism, in regards to both his own thinking and that of others.
With this sobering realization it became clear that to productively engage in philosophy, the philosopher needs to take active steps to mitigate this inherent fallibility that is present in all human beings, including philosophers. So it does not matter the subject that the philosopher sets his mind to, what the particular question is, what means, methods, and instrumentation may be required, for in all cases, the philosopher must first address and take steps to mitigate the introduction and affects of human error in the investigatory/philosophical process/endeavor. This is all that "science" is, a new and more effective approach to the traditional philosophy of the past, with empiricism being a key component to this new approach.
Also note that I say "mitigate" human error and not eliminate or prevent. This is also a key feature of the new approach as knowledge acquired is not held in terms of being or representing absolute truths, rather, acquired knowledge is held with varying degrees of confidence, which is also a fundamental shift from how philosophy was previously practiced.
This brings us now to your question of whether Theology should be considered an empirical study. This is a prime example that clearly illustrates how the new and improved philosophy was place or defined into a narrow and restrictive box that declared the new philosophy could only be used to address a limited category of questions, and a firewall erected and vigorously defended to prevent the new philosophical approach from being applied to the whole of philosophy.
For us to have any confidence in what Theology has to say, or in the conclusion that it draws, it would have to employ the standards and principles of scientific investigation, which would include an approach of rational skepticism and empiricism. In other words, unless and until error mitigation is employed within the field of Theology, what Theology produces must be taken with a grain of salt.
To challenge the notion of the primacy of empiricism a bit more, what about music, or literary criticism? Do you regard those too as empirical studies?
First, let's be clear that not all of our subjective human experience involves issues of objective truth. There are aspects of life in which the objective true/false dichotomy does not apply, but instead deal with expressions of subjective preference. Aesthetics (Art, Music, Literature) and Morals/Ethics would fall under this category.
The new philosophical approach is still relevant and necessary however, because it is this approach that allows us to demarcate between what can be considered objective, subjective preference, or pure analytic abstraction, and once demarcated, address accordingly. As there are questions and circumstances that can involve all three, it is imperative that these distinctions not be lost if one wants a hope of mitigating human fallibility in trying to answer such questions or address these more complex circumstances effectively.
So, in regards to music, one can make empirical observations, use factual data to describe and categorize music, but what should be considered "good" or have "value" comes down to subjective preference, with such preference influenced by both physical biology, cultural conditioning, and personal experiences. In other words, the answer rests solely within the eye of the beholder.
Literary criticism or analysis could be done within the standards and principles of what I have been calling "the new philosophical approach", carefully teasing out the objective, subjective preference, and pure analytic abstractions, or it can simply be a subjective expression regarding someone else's literary subjective expression.
