Tetraethyl lead (TEL) was introduced in the 20s, but was largely eliminated from passenger cars in the US by the end of the 70s, and banned in the 90s. You can still get TEL additives for fuels for certain classic cars that require it, and certain aviation fuels still have TEL because they haven’t found anything else that works in those applications yet.
You can blame Thomas Midgely Jr. for the introduction of both TEL and chrlorofluorocarbons (CFCs used in refrigerants).