Can the ancestry house of Habsburg be traced to Roman times (not necessarily to Rome itself) or does the known line begin only in around 1000? Even if there is no credible evidence, did the Habsburgs themselves ever claim descent from figures of antiquity?
Thanks
They aren't, because nobody can really claim descent from a specific ancestor in antiquity, but like every medieval royal family, they certainly believed they could and there were various routes of descent.
“Shortly after the royal election of 1273, the Habsburgs ordered the deliberate embellishment of their origins since they were pained by their relative humble extraction and parvenu status.” pg 8
(Jean Berenger, C.A. Simpson, A History of the Habsburg Empire, 1273-1700, Routledge, 2014, pg. 8)
Initially they claimed to be descended from the Colonna family of Rome, which was a powerful family in medieval Italy that itself claimed descent from Julius Caesar. Another theory connected them to the Italian Pierleoni family, which seems less prestigious, but it was the family of Pope Gregory I and St. Benedict, so it made them seem religiously significant. And if being connected to the history of the church was not good enough or not prestigious enough (or not politically expedient), there was also a third claim that they were related to the Trojans (as the French dynasties also claimed, through the Frankish Carolingians and the Merovingians). This was the favourite theory of Maximilian I in the early 16th century. It was also a claim to Roman ancestry since Julius Caesar was supposed to be descended from the Trojan Aeneas, as everyone knew from the Aeneid.
In reality no one actually knows where the Habsburgs came from, except that the original Habsburg castle in Aargau in Switzerland was built around 1020, and the earliest known ancestor may have been (but also may not have been) Gontran the Rich, a minor lord who rebelled against Emperor Otto in 952 (Berenger and Simpson, pg. 11). Gontran's ancestors are unknown so the line stops there (if, indeed, it can actually be traced back that far at all).
Troy was the preferred source in England as well, as the British were believed to be descended from Brutus, a descendant of Aeneas. Everyone had to be descended from someone from classical literature no matter how obviously mythological it seemed to later historians!
Another excellent source for this question is Marie Tanner, The Last Descendant of Aeneas: The Hapsburgs and the Mythic Image of the Emperor (Yale University Press, 1993).