True, shampoo was invented in India.
In the 17th century Indians were already very good in the medicinal field and they developed their own system called Ayurveda. By creating this system they managed to develop a liquid (Ayurvedic extract), this was the very earliest effective shampoo to cleanse the hair!
To be able to create this cleansing liquid they boiled sapindus (soapberry) together with dried Aamla, and some other herbs. To then use the remaining sieved extract.
Till this day, people are still creating their own DIY shampoo this way.
The English name shampoo originates from the Hindu word champoo/champu, meaning head massage with oil.
This Indian head message with oil treatment became popular in the rest of the world thanks to Sake Dean Mahomed. Around 1800 he moved with his family to England to start his own bathhouse where he would give customers his special medicinal champoo treatment.
-Sources that we used –
Pratik Hirve – https://tinyurl.com/4jnzzdun
Thebetterindia – https://tinyurl.com/nvb7cunr
Wiki – https://tinyurl.com/5yb6tpke
Atlasobscura – https://tinyurl.com/43dm9ssh