Did Jesus walk on water? Twelve guys saw him do it, according to three reliable accounts. If we accept it, it's history. Those who reject it can write their own histories. No problem. Fair's fair. It really is just as simple as that. Physical miracles are easy to deal with.
But what about SPIRIT? Even trusting the Gospels, how do we deal with their attestations of spiritual phenomena, historically? I suggest that depends upon what spirit is. If scriptural language about spirituality is taken metaphorically, theoretically, symbolically or (sometimes) "theologically", then we have an impassable difficulty. History deals with events, occurrences, behavior, objective reality - anything which the evidence demonstrates did or at least might have actually happened. So for those whose interpretation of SPIRIT is non-actual, nothing spiritual can be considered historical.
Others will merely object that history must deal with physical occurrences only, but this is false because psychological considerations have always been part of historical work. Did the Romans intend to take Macedonia as early as the late 3rd Century BC? At what point did that Republican Senate embrace its role as the new hegemon in the world? Psychological questions like these are what actually drives much of historical inquiry, and whenever psychological conclusions are reached, however qualified they may be, they hold absolute sway over our view of the physical events.
Historians must begin with physical evidence and eyewitness testimony, but not even the staunchest historical-critical scholar restricts themselves to purely physical considerations. Events demand as much explanation as possible, and so the psyches of historical figures must be probed (to whatever degree might be possible in any particular case). Psychological considerations should be formed primarily on the basis of behavioral analysis, based on written accounts, but historians must also consider as evidence the personal opinions and testimony found in those records - just like Psychologists do.
Psychological data is valid because it is actual. The psychic material inside human beings is not physical, but it is very real. The depression Augustus Caesar fell into so deeply in 9 AD was caused by several years worth of events and it strengthened his personal need to rely more on Tiberius. Barring that, if the Emperor's last grandson Agrippa had not become so distemperate, history might have gone very differently. Such psychological factors are not always easy to distinguish precisely, but they are significant and contributing factors in history. To the point, Caesar's depression and Agrippa's distemperance were significant events in their own right.
For related considerations, see my post of a week ago: Psychology & Pneumatology but my main point in all this is very simple. If historians can validly deal with psyche there may also be some valid way to deal with spirit.
Specifically, therefore, here is what I am proposing. IF we consider the spiritual phenomena attested by the Gospel writers to have been an actual part of their objective reality, AND IF we can assess that reality through the record of their testimony, AND IF we can determine from their experiences, more precisely, what SPIRIT is, THEN spiritual events can absolutely be included within the bounds of historical reconstruction.
To put that another way: if the SPIRITUAL elements found in scripture were [and are] actual, instead of theoretical, then any faith-based historiography of the scriptures should consider attestations of spiritual phenomena as historical events.
This also happens to show, once again, that there is no cause for dividing the content of the scriptures between "theological" and "historical" categories... that is, unless we believe some "theological" things were not actually actual.