Roman Emperor (Principate) Antony's daughter who was also Augustus' niece, Germanicus Julius Caesar. Germanicus married Vipsania Agrippina, Agrippa's daughter by Julia and Tiberius's stepdaughter, and had by her one surviving son, Gaius "Caligula" ("Little Boots"), and a daughter, Julia Agrippina, whose third husband was Germanicus's brother by blood, Claudius (she was his fourth wife); Agrippina had already borne a son, Lucius, whom Claudius adopted under the name Nero"' in 40; Nero married Claudius's daughter Claudia Octavia in 53. The year 69 is often called the "Year of the Four Emperors" because it saw four usurpers successively claim the purple robe. The fourth Emperor,
Roman emperor to style themselves as Emperor of the Romans (later βασιλεύς Ῥωμαίων in Greek), but are often referred to in modern scholarship as Byzantine emperors. Constantine XI Palaiologos was the last Roman emperor in Constantinople, dying in the Fall of Constantinople to the Ottomans in 1453. The "Byzantine" emperors from Heraclius in 629 and onwards adopted the title of "basileus" (), which had originally meant "king" in Greek but became a title reserved solely for the Roman emperor and the ruler of the Sasanian Empire. Other kings were then referred to as "rēgas". In addition to their pontifical office, some emperors