What event did Ancient Rome base their calendar years on? For instance, what year was it to the Romans the day Julius Caesar was killed? | AskHistorians Archive Observer

What event did Ancient Rome base their calendar years on? For instance, what year was it to the Romans the day Julius Caesar was killed?

by rewdea

We seem to have based our years starting from 1AD, because Jesus. What event (or events?) was the foundation for Ancient Rome to start counting their years from? If not an event, what was their rationale for what year it was?

MarcusAureliusCotta

They indeed often used to count the years since the speculated date of the foundation of Rome (Ab urbe condita). Years were also dated by the names of the two Romans consuls (the highest office before the emperors and dictators) of the year.