Agrippina the Younger outraged by Claudius' adoption of Nero and his choice of Nero as successor, instead of choosing his own son Britannicus. Nero and Octavia were married on June 9, 53. Claudius later repented of marrying Agrippina and adopting Nero, began to favor Britannicus, and started preparing him for the throne. His actions allegedly gave Agrippina a motive to eliminate Claudius. The ancient sources say she poisoned Claudius on October 13, 54 with a plate of deadly mushrooms at a banquet, thus enabling Nero to quickly take the throne as emperor. Accounts vary wildly with regard to this private incident and according
Roman emperor not recognize him as "Basileus" of the Romans, however, which was a title that he reserved for himself. This line of Roman emperors was actually generally Germanic rather than Roman, but maintained their Roman-ness as a matter of principle. These emperors used a variety of titles (most frequently ""Imperator Augustus"") before finally settling on "Imperator Romanus Electus" ("Elected Roman Emperor"). Historians customarily assign them the title "Holy Roman Emperor", which has a basis in actual historical usage, and treat their "Holy Roman Empire" as a separate institution. To Latin Catholics of the time, the Pope was the temporal authority as