I love Zep. Everyone knows Whole Lotta Love, Stairway, etc, but bear this in mind, and compare to the "big" bands over the last 20 years.
Between Jan 1969, and Oct 1971, they did this;
4 albums, 2 of which are considered as total classics, (II & IV. Prefer III myself). IV is one of the top selling albums of all time. They went from being totally unknown, apart from Jimmy Page, to the biggest selling/grossing/touring band in the world, breaking sales and concert attendances set by the Beatles.
So, global domination, squillions of record sales, and 2 of the best selling rock albums, (including perhaps 4 all time classic tracks) in history. From scratch. In 3 years.
Nearest equivalent?