Soap through the Ages

In researching for my current work-in-progress, I ventured into the world of early sanitation, and interestingly, found the earliest reference to soap was in the 4th c., when Galen, that great medical researcher, said people should use it to keep impurities from the body. During the middle ages, they knew to cleanse their hands before eating, but they only dipped them in perfumed water, which was better than nothing, but I suspect it was to get rid of unsightly dirt rather than to cleanse.

One of the earliest uses of soap was to prepare wool for weaving. Later, soap began to be an elemental part of bathing, and soap-making guilds became prominent in Italy and Spain. Soap-making was sometimes considered “women’s work”, although as it became a prized commodity the skill became one of craftsmanship, with one soap-maker trying to outdo the next with softening agents.

Gradually, coloring agents and perfumes were added, and soap was sold in both liquid and solid forms. Today, Marseille and Castile soap are made from mostly olive oil, and are considered more pure than soaps with harsher chemicals.

In the tenth century, soap was a minor luxury, and cost about one-third of a dinar (dinero, denier).

A Persian chemist wrote recipes for making soap, as did other soap-makers. Here is a recipe from a thirteenth century document:

Take sesame oil, a sprinkle of potash, alkali, and some lime, mix together and boil. Pour into molds and leave to harden. Surprisingly, this is not a lot different from the current process, except for the addition of perfumes.