[OED:] 7. Freq. as Romantic. Designating, relating to, or characteristic of a movement or style during the late 18th and 19th centuries in Europe marked by an emphasis on feeling, individuality, and passion rather than classical form and order, and typically preferring grandeur, picturesqueness, or naturalness to finish and proportion. Generally opposed to classical (see classical adj. 7).
My following questions concern only the definition 7 above: 1. Precisely which (of the many etymons with the root 'roman') were the etymon(s) of 'Romanticism'?
2. How did the etymon(s) of 'Romanticism' shift semantically into defn. 7 above?
Per Wikipedia, 'the group of words with the root "Roman" in the various European languages, such as romance and Romanesque, has a complicated history.' So the excessive number of possible etymons precludes even conjecture: is it the Latin Romanicus, Vulgar Latin *romanice scribere, Old French romanz, etc?
Etymonline and OED do not answer these questions. OED specifies the etymons only of: 'romance' (noun) (summarised in this Quora answer), and Romance (adjective) for Romance languages.
Best Answer
The original stem is "Romant", or "in the manner of Romans".
Languages derived from Latin such as French, Italian and Spanish the term "Romant" or, in old French "Romanz" was used to describe them. Traditionally tragedies or heroic stories would still be presented in Latin or Greek (classics) while other fantasies (including love stories and knight epics) would be presented in Romanz.
Eventually the term was distilled to simply refer to stories which concentrated on aspects of love.
That gives you the root of the movement referred to as "Romanticisim".