From Wikipedia
Corinthian leather was a phrase invented for marketing use to describe the leather used in certain Chrysler luxury cars in the 1970s. In this case, "Corinthian" does not actually indicate any relationship with Corinth, nor any specific type of leather and was added simply as a linguistic cachet.
The first use of this term was to describe the leather in the 1974 Chrysler Imperial, but the best known use of this term is from the advertising campaign for the 1976 Chrysler Cordoba, featuring celebrity spokesman Ricardo Montalbán.[1]
Although many misquote Montalbán as saying "rich Corinthian leather" or "fine Corinthian leather" in the commercial, he actually says that "soft Corinthian leather" is an available upholstery option for the car.[1]
Corinthian leather is a marketing term that does not actually indicate any particular type of leather. Montalbán confirmed this during an interview with David Letterman[when?], admitting that Corinthian leather means "nothing." According to one reference[who?], Chrysler's "Corinthian" leather was mass produced in a plant in Newark, New Jersey.