Jennings was born in 1791 in New York, and was a leader of the abolitionist movement.
He began his career as a tailor. Inspired by frequent requests for cleaning advice, he began researching cleaning solutions.
He started experimenting with different cleaning solutions and products. He tested them on different fabrics until he found the right combination to treat and clean them. He called his method « Dry Scouring, » a process now known as dry cleaning.
Jennings was 30 years old when he received his patent on March 3, 1821, becoming the first African American inventor to own the rights to his invention.