Savon de Marseille

Marseille soap, or Savon de Marseille, is as French as wine and cheese, with a history that dates from the Middle Ages. Frenchwomen swear by the crude square blocks, which they use as a natural skin cleanser and, in a pinch, as anything from a toothpaste substitute to a moth repellent(2).
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1688

Since as early as the ninth century, master soap makers in Marseille have created exquisite, gentle soaps using native olive oils and the alkaline ash from marine plants of the Mediterranean.

However, it wasn’t until 1688 and an edict under the mercantilist policies of Jean-Baptiste Colbert that these fine soaps — containing 72% vegetable oils with no animal additives — came to be known as “Savon de Marseille” (Marseille Soap). Marseille Soap’s popularity continued through the 1700s. In the 1880s the number of soap works in the region peaked at nearly one hundred(1).

1900s

The early 1900s brought the arrival of mass-produced synthetic soaps and detergents. Washing machines made soap blocks less necessary in every home, but many households continued to trust only the purity and gentleness of the authentic green and white soaps from Marseille to wash everything from linens and floors to little faces(1).

Now

Now less than five soap makers still craft Marseille Soap according to the centuries-old tradition. It takes our Maitre de Savon (soapmaster) two weeks to make Savon de Marseille. The delicate mixture of olive oil, alkaline ash from sea plants and Mediterranean Sea salted water are heated for ten days in antique cauldrons, then poured into open pits where it hardens(1).

source:

1. www.savondemarseille.com - Copyright French Soaps LTD 2017

2. https://www.nytimes.com/2016/08/03/world/what-in-the-world/france-savon-de-marseille-recipe.html