Place names do change over time. That a place had different names at different time does not also necessarily mean that that place did not physically exist. Archaeological evidence supports the existence of a town where Nazareth is today. 'Jesus of Nazareth' is one of the many traditional names for the mythic personage who may or may not be historical. Affixing linguistically appropriate or historically accurate names to the mythic figure is mixing these distinct forms of narrative. Myth is not history. That Jesus is 'from Nazareth' is an attribution of theological significance, as is his being of the line of David, and born in Bethlehem.
The search for the historical Jesus was of compelling academic interest in the late 19th and early 20th century. When I was at McCormick Theological Seminary in Chicago (M.Div. 1980) we were more interested in textual analysis, especially the Parables.
The evidence for Jesus being of the Essene community is not compelling. While there may be some 'overlap' of a few Essene beliefs present in the early Christian community in the Roman province of Palestine, the more interesting (and for me a more fruitful) line of investigation would be the influence of the ethics of first century Judaism, especially Hillel on the early church. The primary Christian source material we would have for either of these investigations would be the documents of the New Testament.
The idea of the Messiah was perhaps one of the most profound influences of Judaism on the western world. "At its root, the term mashiach (Hebrew , "anointed one"; translated into English as "messiah") means any person who was ceremonially anointed with oil in preparation for becoming a priest or king, and when most biblical writers used this term literally, that was all they had in mind" (Invitation to World Religions, Jeffery Brodd, et al, Oxford University Press, Oxford, UK, 2013, page 373). I've been using this textbook in my World Religions course for several years now; it is an excellent introduction to the academic study of religion.
