Did researchers assume parts of Plutarch's Romulus was true? Did researchers assume parts of the mythological Gods and Sons of Gods of Greek, Romam,Persian, Egyptian, Jewish mythology was true.
Yes, at one time researchers did exactly that. In fact this idea even has a name:
Euhemerism.
"Perhaps the greatest Miner issue is the fact that all claims of evidence must take into account the mind set of the day. Herodotus (c484 – 425 BCE), the father of history, had argued that
myths were distorted accounts of real historical events. Euhemerus (4th century - 3rd century BCE) took that idea and kicked it up to the next level suggesting that
all myths had some basis in historical fact.
"The work is of immense importance, for Euhemerus proposes that myth is history in disguise,
that deities were originally living men and women who were elevated to divine status because of heroic feats when alive."
The statement "Osiris, Attis, Adonis were men. They died as men; they rose as gods." captures this mind set perfectly." (Rationalwiki's
Evidence for the historical existence of Jesus Christ article; internal references removed for ease of reading)
Here is an actually example of Euhemerism from Plato:
"Phaedrus: Tell me, Socrates, isn't it from somewhere near this stretch of the Ilisus that people say Boreas carried Orithuia away?
Socrates: So they say.
Phaedrus: Couldn't this be the very spot? The stream is lovely, pure and clear: just right for girls to be playing nearby.
Socrates: No, it is two or three hundred yards farther downstream, where one crosses to get to the district of Arga. I think there is even an altar to Boreas there.
Phaedrus: I hadn't noticed it. But tell me, Socrates, in the name of Zeus, do you really believe that legend is true?
Socrates: Actually, it would not be out of place for me to reject it, as our intellectuals do. I could then tell a clever story: I could claim that a gust of the North Wind blew her over the rocks where she was playing with Pharmaceia; and once she was killed that way people said she had been carried off by Boreas..." (Plato, Phaedr. 229b-d, translation taken from: Plato (1997). Cooper, John Madison; Hutchinson, D.S., eds. Complete works. Hackett Publishing. p. 1808. ISBN 978-0-87220-349-5.)
The wikipedia article on Euhemerism has this:
"Euhemerus argued that
Zeus was a mortal king who died on Crete, and that his tomb could still be found there with the inscription bearing his name (Zeus Is Dead: Euhemerus and Crete, S. Spyridakis, The Classical Journal, Vol. 63, No. 8, May, 1968, pp. 337-340.) This claim however did not originate with Euhemerus, as the general sentiment of Crete during the time of Epimenides of Knossos (c. 600 BCE) was that Zeus was buried somewhere in Crete."
Why are people attempting to historicize a blatant mythological character called Jesus is beyond me?
Because that is how history for the majority of it existence worked;
all myth are distortions of actual events.
Why don't they historicize Plutarch's Romulus? He was the mythological founder of Rome born of a woman with a human brother who ascended to heaven after his body vanished when he died. On the day Romulus died there was darkness--the day was turned into night.
Plutarch's Romulus and NT Jesus are similar Myths.
Plutarch's Romulus didn't need to be historicized...because that was the go to for history.