They are a familiar sight on the banks of the Seine - those faintly weary people manning the dark-green wooden stalls filled with used and new books, postcards, posters, paintings, compact disks, LP’s other pre-digital-era media curiosities. They are Paris bouquinistes - a tribe that has existed (and flourished) since as far back as the mid-16th century , although it was only from the 1790s, when they were first officially recognized , that les bouquinistes gradually came to occupy most embankments on and around the Île de la Cité  - despite organized resistance from the more “orderly” bookstores which, as you may know, are aplenty in Paris.
These familiar stalls, if you look at them closer, may offer an absolutely unfamiliar assortment of rare and used volumes. Out-of-print editions, rare LP’s, limited-run hardback series and simply good books that don’t make their way onto the shelves of the major bookstores are all there, waiting to be discovered by a determined shopper: give them a chance (better yet, a whole afternoon) and see what you can find! In a different epoch, one could buy entire collections confiscated from the clergy or nobility by the revolutionaries. Thankfully, Paris is done with revolutions for now (the odd burning car notwithstanding), so your loot will probably fall somewhat short of that, but who knows... may be it’ll be your lucky day!
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 Wikipedia would want you to believe they only appeared in the late 19th century. Our extensive research indicates otherwise.
 Recognized.. and regulated. As with everything in France, les bouquinistes had to submit to a myriad of rules - for example, each stall has to be open at least 4 days a week, regardless of the weather, there are many restrictions on things they can not sell (regulations designed, in theory, to avoid turning them into souvenir stalls for tourists), and so on.
 Their population varied significantly over the years. Today there are about 250 bouquinistes on all the quais surrounding the Île de la Cité.