↑ His ordinal and nickname comes from the fact that he was the second Louis to be emperor after his grandfather Louis the Pious.
↑ Louis's usual title was imperator augustus ("august emperor"), but he used imperator Romanorum after his conquest of Bari in 871, which led to poor relations with Byzantium. He was called imperator Italiae ("emperor of Italy") in West Francia while the Byzantines called him Basileus Phrangias ("Emperor of the Franks").
