Wales entered directly into Manx political history during the crisis of 1651, when Parliamentary authorities feared coordinated Royalist risings around the Irish Sea.

Intelligence reaching the Council of State described a plot involving supporters in Cheshire, Lancashire and North Wales. Mann was still controlled by James Stanley, Earl of Derby, and the government feared that troops from the Island might land in Lancashire or North Wales to support the rising.

Vessels were therefore sent towards Mann to prevent a landing. Colonel Robert Blake was appointed to command a squadron of twelve ships intended for the Isle of Man and the Irish Sea, while other naval commanders were ordered to keep watch on the Island.

The Council also instructed Justice Mackworth in Montgomeryshire to coordinate with militia commissioners and military commanders in North Wales. He was specifically warned that Royalist plans included the possibility of forces arriving from Mann and was told to maintain communication with the Governor of Anglesey.

The surviving records show North Wales and Mann being treated as connected parts of the same Irish Sea security problem immediately before the Parliamentary conquest of the Island.