However, it's a moot point today, since the ducal branch of the house of Wittelsbach is officially extinct. So the line of succession to the defunct throne consists exclusively princes of Bavaria, no dukes in Bavaria. If the male-line descent of King Ludwig I were to become extinct, would a princess succeed?
I ask this because I vaguely heard of some morganatic branch of the house called L÷wenstein, whose members might claim succession rights. The official line today seems to end with the Prince Hubertus (b. 1986). What I'm unclear about, however, is the status of his cousin Manuel -- born out-of-wedlock in 1972. He has since been legitimized through the marriage of his parents. And he himself made things very interesting by marrying a born princess, Anna of Sayn-Wittgenstein-Berleburg.
By today's standards, the union of a royal and a member of a mediatized house is considered *good*, even though before World War I it would simply have been acceptable.
But while Manuel is styled as a prince of Bavaria, with the qualification of Royal Highness, I don't know if he and his sons are in the succession -- or excluded because he was originally illegitimate. If British rules applied, exclusion applies even to persons legitimized after being born out-of-wedlock. I'm not sure about German house rules, though: having a title is not necessarily indicative of succession rights. We have seen numerous cases in royal houses of persons with titles but no succession rights, and vice versa.