How did George Clooney get famous?

After guest appearances in the TV shows "Facts of Life", "Roseanne" and "Sisters", his big break came as a regular actor in "ER" in 1994, playing Dr. Doug Ross.

George Clooney had some guest appearances on tv shows such as Roseanne, but he acquired his first big role in 1994 as Dr. Doug Ross in ER. Afterwards he became well-known for being a great actor.