One possible origin is Jack Donahue (also spelled Donohoe), an 1820s Irish convict who was sent to Australia, became a bushranger and was killed by police.
[2] Another possibility is that the song refers to an 1860s juvenile Australian convict named John Doolan, who was born in Castlemaine, Victoria, and also turned to bushranging.
He was scarcely sixteen years of age when he left his father's home, And through Australia's sunny clime a bushranger did roam.
He stuck up the Beechworth mail-coach, and robbed Judge MacEvoy, Who trembled, and gave up his gold to the wild Colonial Boy.
One day as he was riding the mountain-side along, A-listening to the little birds, their pleasant laughing song, Three mounted troopers rode along – Kelly, Davis and FitzRoy – They thought that they would capture him, the wild Colonial Boy.