Rinso is a brand name of laundry soap and detergent marketed by Unilever. The brand was created by Robert Spear Hudson and originally branded Hudson's Soap, which was sold to Lever Brothers of Port Sunlight, England, in 1908. It was introduced in the United States by Lever Brothers Company in 1918.

Robert Spear Hudson was an English businessman who popularised dry soap powder. His company was very successful thanks to both an increasing demand for soap and his unprecedented levels of advertising. After his death, the company was taken over by his son, and was later purchased by Lever Brothers.