It's a rather murky answer at best but I'll try here goes..... Most of the first automobiles were based on horse-carriges available at the time, many having retractable roofs......ergo the first full bodied cars followed suite.Even though a steam powered car was invented in 1672 by Ferdinand Verbiest it is quite likely the inventor of the first full bodied car would get credit.The convertible was the default body style of all vehicles before 1910, when Cadillac introduced the first closed-body car. James Jones created the patent for the convertible car in 1919. Credit for the first modern hardtop convertible goes to Chrysler -- with a 1946 model. But the first hardtop retractable convertible was invented by B. B. Ellerbeck in 1931. Hope that helps or helps to confuse you even more.crazywowow.