sentences:  In 1296, after John ratified a military treaty with France, and refused to hand over Scottish castles to Edward I's control, the English marched north and crushed the Scots at Dunbar.Edward I's forces proceeded forward virtually unopposed, whereupon Scotland fell under English control.The chief of Clann Dubhghaill in the last quarter of the thirteenth century and first decade of the next was Alasdair Mac Dubhghaill, Lord of Argyll.