Answer: the middle of March (March 15th)
Step-by-step explanation:
When the soothsayer said "Beware the ides of March!", the soothsayer is simply warning Caesar to beware the middle of March (March 15th).
The Ides of March is March 15th. In the Roman Calendar, it is regarded as the 74th day. It was a day that was typically marked with religious observances. It was also utilized as a deadline for debt settlements.