flagpole

n. A person who sits for an extended period of time on top of a flagpole or other high column; -- a publicity stunt performed for various reasons. [ PJC ]

He [ Shipwreck Kelly ] was the great flagpole sitter of the thirties, the founding father of the whole discipline, who provided inspiration for many and even the pseudonym for one -- Van Nolan, who also called himself Shipwreck. Any serious polesitter believes himself an avatar of Shipwreck Kelly, and I was then and am now no exception. From: John A. Gould, Aerie (Berkshire Review, Volume XI, Number 1, Spring, 1975).

The two other holy men in Gregory's narrative had more exotic origins than the pair that has just been seen. Gregory encountered one of them when on a journey to the north-eastern parts of the Frankish kingdom. This was a Lombard, named Vulfolaic, who had spent some years in the arduous exercise of being a stylite, the Christian equivalent of a flagpole sitter; in other words, Vulfolaic was a monk whose main austerity consisted in living on top of a pillar. By carrying out this feat in the rain, snow, and frost of the Moselle valley, Vulfolaic had convinced the local population to overthrow and abandon the idol of Diana to which they were addicted. Walter Goffart, FOREIGNERS IN THE HISTORIES OF GREGORY OF TOURS (https://journals.lib.unb.ca/index.php/flor/article/download/15346/20501).