Both manga depict the story of Cesare Borgia. However, that's about where the similarities end. "Cantarella" is more supernatural shoujo-fantasy, with Cesare depicted as a tragic figure, who wields demonic power at the cost of his humanity. Historical events are followed loosely, and Renaissance Italy is a sort of backdrop for the often romantic-themed conflicts between the characters, all told with beautiful, flowing artwork. "Cesare" is also a bit dark, but in a way that there's more focus on political atmospheres and struggles, and Cesare himself is more of a charismatic figure whose power begins with his intellect.
Both are about the historical Italian, Cesare Borgia, and the people, politics, and intrigues surrounding him. Cesare is a realistic story, whereas Cantarella is a more fanciful version, with shounen-ai, and some supernatural elements.
It's easy to identify the similarities between Cesare and Legend of the Galactic Heroes. For instance, Cesare and Reinhard are similar in the sense that they come from a long line of history and families (i.e. Cesare as the son of Rodrigo Borgia and Reinhard as the son of Rudolf Von Goldenbaumm) and are ambitious to lead a world of their own as rulers of their respected countries. They eventually do so in the process, but they wound up falling flat down to their defeat.
Their protégés, Angelo da Canossa and Siegfried Kircheis are similar because they are naïve at times and remain so in the remainder of the story. If you enjoy manga or novels with a sense of political intrigue, an emphasis on ideas of philosophy, math, science, literature, etc., then this is the manga for you. read more
Even though at the beginning it appears to be a simple manga they both develop eventually in political mangas having a greater plot spanning the whole story.
They both give off the same vibe and are just superb.
First of all the same author thus the same type of story telling which is quite scientific and very well documented.The characters have amazing depth to their personalities and it goes the same for the scene where the actions take place.The way it is done just makes you feel you are there,really understanding what the author tried to express thus participating and empathizing along with the rest of the world created.
So if you want something smart,serious,enchanting and especially something that makes you think again,you should go for this Eternal Sabbath and if you liked this one you will love Cesare.