England have the most Six Nations titles in the tournament's current format. They've won the Championship Trophy seven times, with Wales and France close behind on six apiece, followed by Ireland on five.
However, the tournament has worn several guises over the years. It started out as the Home Nations in 1883, before becoming the Five Nations in 1910, returning to its previous state again in 1932, expanding to Five Nations again in 1940, and eventually growing to Six Nations in 2000.
England have won 29 overall titles, one more than Wales. France have won 18, Ireland 15 and Scotland 14.