tannare

Medieval Latin tannare meant to tan — to treat hides with tannin extracted from oak bark. Tannin came from the bark (cortex) of oak, chestnut, and other trees; the name appears in French documents from the 8th century. The process involved soaking hides in pits of increasingly strong tannin solution over several weeks or months, transforming putrescible animal skin into durable leather.

Medieval tanneries occupied specific locations in every town: along rivers (for water to soak hides), downwind of residential areas (tannin and decaying flesh produced powerful smells), near oak forests (for bark). The Tanners' Company in London was established in the 12th century. The tanners of Córdoba in Spain, who produced the Cordwain leather that gives cordwainer its name, were among the most skilled in medieval Europe.

Leather was essential to medieval civilization: boots, saddles, harnesses, armor, books, buckets, and bellows all required it. The tanner's trade was foundational to the entire economic pyramid — without leather, armies could not march, horses could not be ridden, books could not be bound. A society's leather supply was a measure of its productive capacity.

Today industrial tanning uses chromium sulfate rather than vegetable tannins, a method developed in the 1850s. Chrome tanning is faster (hours rather than weeks) and produces softer leather. Traditional vegetable tanning survives in high-end leather goods production — the Hermès saddle-stitched leather bags are vegetable-tanned. The ancient tannin process gives luxury goods their specific smell and quality.