I doubt they invented shampoo as well.....next thing you know, you'll tell me they also invented deodorant, but choose not to use it. 
More copy and paste
Soap, Shampoo, Cleanliness and Cosmetics
The medieval times, was known for its lack of cleanliness and hygiene, leading to illnesses and diseases, and one of the Crusaders most striking characteristics were that they didn’t wash.
Only a few Muslims, as early as the 7th century, had developed a sophisticated and hygienic way of life, and methods to keep themselves clean and away from diseases. In Islam, cleanliness is considered as half of a Muslims relegion. This was motivation for Muslims, also the fact that not keeping clean led to diseases and bad health.
The greatest thing done for cleanliness by Muslims, is probably the invention of soap. The credit for this goes to Muslim chemists. Before the invention of soap, people used oils to clean themselves, but all people didn’t have these oils.
Soap was made by mixing oil (usually olive oil) with al-qali (a salt like substance). This was then boiled to achieve the right mix, and left to harden, before used in homes and public baths.
