The Fiat 1300 and Fiat 1500 are large family cars manufactured by the Italian automaker Fiat Auto from 1961 to 1967, which replaced the Fiat 1200. The 1300 and 1500 were essentially nearly identical, but differed in engine displacement, as indicated by model names. They were available as a saloon and estate, and spawned a convertible version, which shared little mechanically with the other body styles except the 1500 engine.
The 1300/1500 and their derivatives were also assembled by the Yugoslavian Zastava and Fiat's German subsidiary, Neckar Automobil AG. The floorpan of the 1500C was used as a basis for its replacement, the Fiat 125, while another model, the Polski Fiat 125p, made by the Polish FSO, was created by mating the body of 125 and mechanicals (engines, gearbox, transmission, suspension) of 1300/1500. In the Italian range, the 1300 was replaced by the Fiat 124 in 1966, and the 1500 by the Fiat 125 a year later.
Source: Wikipedia, 2011