Who was artemidorus in Julius Caesar?

In Julius Caesar, Artemidorus is a Greek philosopher and scholar who attempts to warn Julius Caesar about the conspiracy to assassinate him. Artemidorus writes a note containing details of the plot and tries to hand it to Caesar as he enters the Senate for the meeting where he is assassinated. However, Caesar is distracted and does not receive the note, leaving him unaware of the danger he is in. Artemidorus' character serves to highlight the inevitability of Caesar's fate and the tragic consequences of his lack of caution in the face of warnings.