The earliest known chess pieces, the Afrasiab pieces, were a figural design; figural chess sets have been made ever since. Figural sets are, basically, sets which represent figures, human, animal, or otherwise. Muslim sets, for example, are completely abstract, the opposite of figural sets.  Most sets fall somewhere in between, with figural knights represented as horses of some kind, and other pieces bearing a closer resemblance to architecture or stylized figures. The Staunton king, for instance, is a classical column with a crown. Is the crown enough for this piece to be considered the figure of a king? I would say no. A few figural sets fall into other categories in this site, Lewis sets, and Rajasthan sets are clearly figural but I've subdivided those designs further. I may change the layout of this site if I get more examples of certain styles of chess sets. It's more or less arbitrary. Anyway, here are some of my figural sets that don't fall into other categories at the moment:

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