Who are the main characters of the highwayman?

The main characters of the story are Beth (the landlord's daughter), and the highwayman.

The main character is The Highwayman

In the Ballad by Alfred Noyes, the Highwayman falls in love with Bess (the Landlord's daughter) and so does a man called Tim the Ostler who overheard the Highwayman talking to Bess.