Alexander II was King of Scotland from 1214 until his death. He concluded the Treaty of York (1237) which defined the boundary between England and Scotland, virtually unchanged today.
Great Seal of Alexander II
Alexander the warrior and knight: the reverse side of Alexander II's Great Seal, enhanced as a 19th-century steel engraving. Legend: Alexander Deo rectore Rex Scottorum (Alexander, with God as his guide, king of the Scots)
Coat of arms of Alexander II as it appears on folio 146v of Royal MS 14 C VII (Historia Anglorum). The inverted shield represents the king's death in 1249. The blazon for the arms was Or, a lion rampant and an orle fleury gules.[self-published source?]
The Treaty of York was an agreement between the kings Henry III of England and Alexander II of Scotland, signed at York on 25 September 1237, which affirmed that Northumberland, Cumberland, and Westmorland were subject to English sovereignty. This established the Anglo-Scottish border in a form that remains almost unchanged to modern times. The treaty detailed the future status of several feudal properties and addressed other issues between the two kings, and historically marked the end of the Kingdom of Scotland's attempts to extend its frontier southward.
Steel engraving and enhancement of the Great Seal of Alexander II
Engraving of Henry's great seal