Honor Among Thieves

From the chapter on Gypsies in Manners, Customs, and Dress during the Middle Ages and during the Renaissance, by Paul Lacroix (free on Kindle):

This alliance--governed by statutes, the honour of compiling which has been given to a certain Ragot, who styled himself captain--was composed of matois, or sharpers; of mercelots, or hawkers, who were very little better than the former; of gueux, or dishonest beggars, and of a host of other swindlers, constituting the order or hierarchy of the Argot, or Slang people.
 Their chief was called the Grand Coesre, "a vagabond broken to all the tricks of his trade," says M. Francisque Michel, and who frequently ended his days on the rack or the gibbet. History has furnished us with the story of a "miserable cripple" who used to sit in a wooden bowl, and who, after having been Grand Coesre for three years, was broken alive on the wheel at Bordeaux for his crimes.
One of his successors, the Grand Coesre surnamed Anacréon, who suffered from the same infirmity, namely, that of a cripple, rode about Paris on a donkey begging. He generally held his court on the Port-au-Foin, where he sat on his throne dressed in a mantle made of a thousand pieces.
The Grand Coesre had a lieutenant in each province called cagou, whose business it was to initiate apprentices in the secrets of the craft, and who looked after, in different localities, those whom the chief had entrusted to his care. He gave an account of the property he received in thus exercising his stewardship, and of the money as well as of the clothing which he took from the Argotiers who refused to recognise his authority.
As a remuneration for their duties, the cagoux were exempt from all tribute to their chief; they received their share of the property taken from persons whom they had ordered to be robbed, and they were free to beg in any way they pleased.

After the cagoux came the archisuppôts, who, being recruited from the lowest dregs of the clergy and others who had been in a better position, were, so to speak, the teachers of the law. To them was intrusted the duty of instructing the less experienced rogues, and of determining the language of Slang; and, as a reward for their good and loyal services, they had the right of begging without paying any fees to their chiefs.
The Grand Coesre levied a tax of twenty-four sous per annum upon the young rogues, who went about the streets pretending to shed tears, as "helpless orphans," in order to excite public sympathy. The marcandiers had to pay an écu; they were tramps clothed in a tolerably good doublet, who passed themselves off as merchants ruined by war, by fire, or by having been robbed on the highway. The malingreux had to pay forty sous; they were covered with sores, most of which were self-inflicted, or they pretended to have swellings of some kind, and stated that they were about to undertake a pilgrimage to St. Méen, in Brittany, in order to be cured.
Besides these, there were the callots, who were either affected with a scurfy disease or pretended to be so, and who were contributors to the civil list of their chief to the amount of sevens sous; as also the coquillards, or pretended pilgrims of St. James or St. Michael; and the hubins, who, according to the forged certificate which they carried with them, were going to, or returning from, St. Hubert, after having been bitten by a mad dog.
The polissons paid two écus to the Coesre, but they earned a considerable amount, especially in winter; for benevolent people, touched with their destitution and half-nakedness, gave them sometimes a doublet, sometimes a shirt, or some other article of clothing, which of course they immediately sold.
The francs mitoux, who were never taxed above five sous, were sickly members of the fraternity, or at all events pretended to be such; they tied their arms above the elbow so as to stop the pulse, and fell down apparently fainting on the public footpaths. We must also mention the ruffés and the millards, who went into the country in groups begging.
The courtauds de boutanche pretended to be workmen, and were to be met with everywhere with the tools of their craft on their back, though they never used them.
The convertis pretended to have been impressed by the exhortations of some excellent preacher, and made a public profession of faith; they afterwards stationed themselves at church doors, as recently converted Catholics, and in this way received liberal contributions. Lastly, we must mention the drilles, the narquois, or the people of the petite flambe, who for the most part were old pensioners, and who begged in the streets from house to house, with their swords at their sides.
These, who at times lived a racketing and luxurious life, at last rebelled against the Grand Coesre, and would no longer be reckoned among his subjects--a step which gave a considerable shock to the Argotic monarchy.