Final answer:
Julius Caesar received multiple letters warning him of the conspiracy on the Ides of March, 44 BCE, with Artemidorus being one known individual who attempted to deliver such a warning.
Step-by-step explanation:
The question "Who else has given Caesar a letter on the day of his assassination?" refers to the events of March 15, 44 BCE, known as the Ides of March, when Julius Caesar was assassinated by a group of senators. On that day, numerous warnings and letters were delivered to Caesar, cautioning him against potential threats. One of the individuals who is known to have handed a letter to Caesar on that day was Artemidorus. In William Shakespeare's play 'Julius Caesar,' Artemidorus attempts to warn Caesar with a letter that outlines the conspiracy against him, though Caesar never reads it. This dramatic portrayal is based on historical accounts, suggesting that Caesar did indeed receive various letters, although the specifics of who handed them to him and their contents might not be as clearly documented outside of Shakespeare's interpretation.