Where did espadrilles really originate?
In the XIIIth century, espadrilles were already used as footwear for the King of Aragon's footsoldiers. They were hand made, with soles of esparto or other grass rope. The uppers were of fabric woven from flax, (not cotton in those days!). Pitch was used to protect the undersides of the soles.
By the XVIIIth century, the town of Mauléon, in the viscounty of Soule (now part of Pyrénées-Atlantique) was a centre for the manufacture of espadrilles. They were still hand made, by craftsmen working from home.
In the early XIXth century, Mauléon started collecting and selling the craftsmen's output in quantity. By 1880, more and more espadrilles were made in factories.
The biggest volume of espadrilles was sold to mineworkers in northern France. Since they only lasted a few weeks, demand was high. There were about 30 factories in the old viscounty of Soule.
During this period, factories started exporting espadrilles, particularly to South America.
By 1911, factories had consolidated and grown larger. There were 9 in Mauléon, employing 1600 workers. Many of these were the migrant workers known as 'hirondelles' (swallows), young girls from Aragon and Navarre who came during the summer.
Around 1980, competition from Asian countries started to hit the region, and now there are only a few small family businesses still upholding the old traditions.
In 2007, I saw signs that some are beginning to strike back by catering for small-volume production, using inkjet-printed fabrics designed by young artists. Modern technology may be the lifeline that saves them from falling to the competition from high-volume, low-cost Asian sources.
Here's an excellent video report made at one of the small espadrille-making factories in Mauléon. Even if you can't understand the French dialogue, you'll get an excellent idea about how espadrilles are made.