In 1978, there were only four gangs in Liberty City. The Uptown Yardies had not been formed yet, the Cartel did not arrive yet, along with the Yakuza. The largest gang at the time was the Forelli Family - the smallest being the Wichita Gardens Syndicate.
This is a list of the four gangs in 1978.
Forelli Family - The largest mafia family in the city in 1978, they were the first of their kind to start in the city, formed in 1954 just before the Leone family. They both have been a rivalry, but not enough to bring them both into a gang war. After Sonny Forelli's death in 1986, their power substantially fell and most of their territory was gone by 1990. By 2000, they would disband almost completely and would lose all of their turf.
Leone Family - They came from Sicily just after the Forellis in 1954, with more power than the Forellis at first. But soon they would lose a lot of turf, even though they are not that weak in 1978. At the time, Salvatore is a hitman and not the don. He would become the don in the 1980's. Both the Forelli's and the Leone's have some turf in Fort Staunton, while the Leone's also have some in Torrington.
Triads - This gang has been around for nearly as long as Chinatown, formed in about 1880 by some Chinese immigrants. They have always had turf in the place they started from, plus have some turf in Callahan Point. Most of them are fearless and always start a fight with their rivals. Right after the events of this game, they build a fish factory in Trenton which would be targeted twice in the following years.
Wichita Gardens Syndicate - So far they are the newest and smallest gang in the city, with just turf in Wichita Gardens and some of Cedar Grove. They were formed in 1973 by Master King. The gang's aggressiveness would cost them a lot, with a huge amount of casualties from a brief gang war.
Federico Gillidarto - Age 49, the don of the Leone Family.
Sonny Forelli - Age 37, the don of the Forelli Family.
Tent "Master King" Harleston - Age 30, the leader of the Wichita Gardens Syndicate
The Triads have no official leader, as they are really an underground society.