The developments spread to Anglo-Norman possessions in Ireland where this English style of castles dominated throughout the 13th century, although the deteriorating Irish economy of the 14th century brought this wave of building to an end. In Scotland Alexander II and Alexander III undertook a number of castle building projects in the modern style, although Alexander III's early death sparked conflict in Scotland and English intervention under Edward I in 1296. In the ensuing wars of Scottish Independence castle building in Scotland altered path, turning away from building larger, more conventional castles with curtain walls. The Scots instead adopted the policy of slighting, or deliberately destroying, castles captured in Scotland from the English to prevent their re-use in subsequent invasions – most of the new Scottish castles built by nobles were of the tower house design; the few larger castles built in Scotland were typically royal castles, built by the Scottish kings.