From which two Latin names did Lewis Carroll derive his pen name?

Lewis Carroll derived his pen name from the Latin names Carolus Ludovicus.

His birth name was Charles Lutwidge Dodgson. Dodgson translated “Charles Lutwidge” into Latin as “Carolus Ludovicus,” then transformed the result back into English and reversed the order. “Carolus” produced Carroll, while “Ludovicus,” the Latin form associated with Lutwidge, produced Lewis. The reversed arrangement became Lewis Carroll.

The pseudonym was not simply an invented fantasy name. It was a carefully constructed literary alias that allowed Dodgson to separate his popular writing from his academic career as a mathematician and lecturer at Christ Church, Oxford.

Dodgson reportedly submitted several possible pseudonyms to the editor Edmund Yates. Lewis Carroll became the name attached to Alice’s Adventures in Wonderland, Through the Looking-Glass, and his nonsense poetry, while he generally used Charles Lutwidge Dodgson for mathematical and scholarly work. “Carolus Dodgson” is therefore not the source pair: the relevant Latinized names are Carolus and Ludovicus.