A long tradition exists in Irish history, literature, and oral storytelling of the deeds of Irish outlaws active during the many decades of oppressive English rule. In the late eighteenth century and early nineteenth century, these outlaws were associated both with Catholic rebel groups and an allied Presbyterian organization, the United Irishmen. These outlaws were constituted as localized cells, with the leaders of each cell taking on menacing-sounding titles of rank: Captain Stout, Captain Whack, Captain Hawk, Captain Dasher, Captain Fearnot, etc. In fact, there was a real “Captain Thunderbolt,” John Duggan, who was captured after a 1799 house raid led by his uncle resulted in a murder. Duggan was brutally executed that same year, about fifteen or sixteen years prior to the supposed fame of Michael Martin’s “Captain Thunderbolt.”
It seems likely that Michael Martin was familiar with some of the classic literature of Irish outlaws: The Life and Adventures of James Freney (1754); Cosgrave’s A genuine history of the lives and actions of the most notorious Irish highwaymen, Tories and Rapparees (1747); and The Life and Adventures of Jeremiah Grant (1816). The Grant title was in print just before Michael Martin departed for America. Though these sources might have inspired Michael Martin, he did not re-use any specific episodes found in these. Martin’s confession relates outlaw adventures that appear to be original. But were they real?
The names of Michael Martin, John Doherty, Captain Lightfoot and Captain Thunderbolt do not appear in any Irish or British newspaper accounts from 1814 through 1819. Nor do any accounts of outlaws in that period match their description. Martin portrays John Doherty (Thunderbolt) as a remarkable figure: tall and muscular, a master of disguise, able to romance any woman (and married five times under different names), a career thief who had never been captured, and well-versed in many disciplines, including medicine. Yet no other publications or commentators describe anyone matching Martin’s description of Doherty. At one point Martin asserts that in 1816 there was a reward of £500 on Doherty’s head. Only a few criminals accused of murder—or attacking uniformed officers, or arson, or heavy forgeries—had such a price put on their capture, and they were well-advertised. Yet no reward offers printed in newspapers of the time match Doherty.
Several of the names that Martin drops cannot be verified: the Martin family’s landlord, Sir William Morris; the widow MacBriar; Colonel Brierton; and the Wilbrook sisters. It is not obvious why he would want to hide the identity of his robbery victims, unless they were fictions. Similarly, Martin offers several clues about his family origins, but an Irish genealogist could not verify any of the information, even given that genealogical records of that period are now scarce.