Even the ancient Greeks had "federalism" in their various leagues, and you could easily argue that the Persian Empire, the early Indian empires, and so on and so forth all used the principles of federalism to govern vast territories.
I should just point out that there is nothing federal about the United Kingdom. In actual fact, ever since it was first instituted in 1707, its tendency has been to centralise power in London.
In the beginning, most day to day issues relating to governance which affected people’s lives were decided at the parish level. Gradually, power started to move towards London and away from local areas, and all sovereignty rests in London. This centralising tendency is one of the reasons btw, that the American colonists rebelled against their London masters and set up their own country, and made sure that the individual states retained sovereignty on certain issues which the federal government was defined to have no competence over (well, until the US Civil War and after, but thats another story)....