Who invented the revolving pistol?

According to PBS, Elisha Collier invented one of the first true revolving flintlock pistols in 1814 and patented it in 1818; however, because it was a flintlock design, it was unreliable. Samuel Colt improved on Collier's design in 1835.

Colt received a patent for his revolving pistol in 1836. The Colt Paterson was a revolving, breech-loading model with a folding trigger and was the first repeating firearm that was practical to manufacture and use. Based on this design, Colt began to mass produce guns, making them affordable to soldiers and pioneers. Colt held a monopoly on the manufacturing of revolvers until 1857.