King of Mountain and Vale
From A Wiki of Ice and Fire
The first King of Mountain and Vale was crowned during the Andal Invasion, over six thousand years ago. The Andals landed at the Fingers, the northeastern shores of the Vale. Led by Ser Artys Arryn, the Winged Knight, they destroyed the last remnants of the children of the forest in the Vale and defeated the "Griffin King", last of the Mountain Kings. This led to the First Men inhabiting the Vale and the mountains to either flee or to intermarry, as in the case of Houses Redfort and Royce.
The Vale was renamed the Vale of Arryn in Ser Artys' honor. He was given the Falcon Crown and became the first King of Mountain and Vale. The Falcon Crown was passed down from Arryn to Arryn until Ronnel Arryn, a boy-king whose mother submitted to the Targaryens during the Wars of Conquest.