What's with all the rakes?
In the early days of historical romance as we know it (post-1972's The Flame and the Flower by Kathleen E. Woodiwiss) the experienced male with a long list of conquests and perhaps an existing mistress was often shorthand for cluing the reader in on what a virile man our hero was. This has been common, but is it strictly necessary? Virgin heroes, like Winter Makepeace in Elizabeth Hoyt's Thief of Shadows, have their own appeal, and it's entirely possible that a desirable man could choose to wait to begin that intimate part of his life. Fear of disease, moral and/or religious conviction, family or cultural tradition or expectation, lack of preferred partners, personal choice, a tight focus on another aspect of life...there are as many reasons as there are individuals, in any time, past, present or future.
On the other hand, it's true that men of the upper classes were not, as a rule, expected to remain chaste (unlike their female counterparts, but that's another topic.) which begs another question. Does a hero need to have a long string of conquests to prove his virility, or does it come from some other source? Is a long term relationship with a wife or mistress enough to establish the hero in this aspect, or is it a different matter when the hero has several past amours? Does the nature, rather than the number, tell more about how our hero will treat our heroine?
Perhaps it's not the facts but the fantasy that makes a rakish hero popular. Does the idea of a heroine being "the one" to tame a notorious rake (and dibs on To Tame a Notorious Rake as a future title; it would sell, dangit.) contribute to the appeal of this trope? With historical romance heroines largely virginal, a first partner who knows what he's doing could be counted as a plus. Then again, there's something special about two people being the other's one and only, discovering the intimate side of love together, a scenario that need not be limited to sweet romance, either.
So, dear readers, what's your pleasure? Is your ideal hero experienced, or about to discover a whole new world? Does it depend on the historical period, class, or subgenre, or does it hinge on the individual alone?
