It's probably not controversial to say that the Dungeons & Dragons game from 1974 was the most important and influential game in the whole genealogy of all RPGs. Every game that followed was either an attempt to make a game that improves on D&D or make a game that is different from D&D. They were either a direct response to D&D, or expanded on a game system that was.
The real question is, what other games can be considered hugely influential on how people design game systems today?
It could depend on which game systems are more famous in your country. Games like Call of Cthulhu and Runequest , both using BRP (a percentile system) were very famous and played in Spain for many years in direct competition of Dungeons & Dragons.