This was the second highest audience rating ever recorded for the tournament on Irish television.
It is second only to Ireland's previous historic win against England at Croke Park in the 2007 RBS 6 Nations, when a peak audience of 1.2 million viewers was recorded during the 77th minute of that match.
In another big weekend for Six Nations fans, France's victory over Wales amassed a peak audience of 536,000 to RTE in the closing moments of the game, while Scotland's meeting with Italy attracted a peak of 266,000 viewers in the second half.