No, not all Roman emperors were called Caesar. The title “Caesar” originated from Julius Caesar, who was a prominent Roman general and statesman. After his assassination in 44 BCE, his adopted heir, Octavian (later known as Augustus), became the first Roman emperor. Augustus and his immediate successors used the title “Caesar” as part of their name to signify their connection to Julius Caesar and to legitimize their rule.
Over time, the title “Caesar” evolved and was used in different ways. In the early Roman Empire, it was often given to the heir apparent or the junior co-emperor. By the time of the later Roman Empire, the title “Caesar” was used more broadly and could be granted to various high-ranking officials or members of the imperial family.
However, not all Roman emperors used the title “Caesar” in their official names. Some emperors chose different titles or names to reflect their unique positions or to distance themselves from previous rulers. For example, the emperor Constantine the Great, who ruled in the 4th century CE, did not use “Caesar” as part of his official title.
In summary, while the title “Caesar” was significant and widely used in the Roman Empire, it was not a universal title for all Roman emperors. The use of the title varied depending on the time period and the individual emperor’s preferences.