In 1430, Henry Ciprian and Roger Bukke, two Augustinian canons, fled from their priory at Waltham, Essex, and sought sanctuary at the collegiate church of St. Martin le Grand in London. Their request for asylum sparked a major conflict between the dean of St. Martin’s and the mayor and aldermen of London over the church’s right to harbour sanctuary seekers, and more broadly to exercise a jurisdiction independent from the City of London.
In the controversy that followed the forcible seizure of the two canons by the sheriffs of London from the church, a flurry of petitions and statements issued from each side presenting their cases to the king’s council. St. Martin’s argued (disingenuously) that the church had offered sanctuary to felons since before the Conquest; the City responded with several equally disingenuous arguments.
The most interesting of the City’s contentions is that since London had been founded by Brutus the Trojan, a refugee from the Trojan wars, its privileges and rule over the territory within the present walls, including St. Martin’s precinct, went back even before the early English established their kingdoms and so predated any royal grants of jurisdiction to St. Martin’s.

Neither side addressed directly the most interesting legal question — whether sanctuary was available for the offence of apostasy, a legal anomaly sitting at the juncture between ecclesiastical and common law. Monks, canons, nuns, and other religious who left their orders without permission were subject to arrest by royal officers in England from the thirteenth century, but the offence itself was not a felony, and thus perhaps sanctuary could not be claimed for it.
This is the only case, to my knowledge, of apostates claiming sanctuary for apostasy (though there are a couple of other cases involving runaway monks), and it did not settle the matter, for no judgment regarding the legality of the canons’ arrest survives. I suspect that the matter remained undecided.
I have not been able to trace what happened to the two canons. I discussed this case in more detail in another blog post for Legal History Miscellany in 2018, which anyone interested in the references can consult.
Top image: Augustinian canons – https://commons.wikimedia.org/wiki/File:Memorial_Tablet_by_the_Master_of_the_Spes_Notra_before_the_2006_restoration.jpg