A question has been raised on the yahoo groups medieval encampments list regarding appropriate furniture for a late period, French, encampment.
I have been looking at extant examples of portable furniture from that period and have found variations of this chair from both England and Spain. I haven't looked at French furniture yet, but I suspect they also have a variation. (FYI, I took a brief look at French furniture yesterday and the form--"Caquetoire Garnie"-- does appear.) Some versions seem to collapse by removing the spreader bars between the sides, others may add or substitue hinges in the spreader bars, and some versions add hinges or other joints halfway down the legs for an additional point of collapse.
I'll add detail of my sources ASAP (NOTE: sources now added), but in the meantime I wanted to share my sketch-up model of a type of chair which I have never seen in my (admittedly limited) experience of SCA camping. To wit,
the Friar's (Monk's) chair
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As usual, if you click on the picture it will take you to sketch-up where you can pivot the view or download the model to tinker with.
Folding sillon frailero of walnut (sixteenth century) 
Musee Episcopal, Vich. Bacelona. "as in many early examples, the frame can be dismounted." From "Furniture Past & Present, L. Boger, Doubleday, 1966
Folding sillon frailero (sixteenth century) 
Spanish Interiors and Furniture: Photographs and Drawings, Arthur Byne and Mildred Stapley, William Helburn, Inc. 1921
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