The last of Leven's army left England at the beginning of February 1647. Selling the king left the covenanted regime further than ever from its goal of a settled peace in a federative union of presbyterian kingdoms. The withdrawal ended the naval provisions of the Solemn League, but the continuing centrality of the naval union to Covenanters’ conception of security meant that by the end of the year it would be repackaged in the Engagement. The whole security rationale of the Covenanters’ union project became more and more unsteady as need for union to provide long-term security for the kirk pushed them towards the deep short-term insecurity of war with parliament, which would lead first to the English breaking the regal union then conquering Scotland itself.

A Change of Sides, Not of Naval Policy

The king spent early 1647 in parliament's custody before being seized by the New Model Army; then on 11 November Charles escaped and, spurning Scottish suggestions of Berwick, made for Carisbrooke on the Isle of Wight. The political ground had been shifting in Scotland for some time; Hamilton had galvanised support for defending the position of the king. The Covenanters had always maintained that they supported royal authority within its traditional limitations, as long as it did not conflict with the kirk. Hamilton failed to stop the sale of the king, but it encouraged some, like John Maitland, now earl of Lauderdale, to join the Hamiltonian/conservative faction, weakening the radicals who followed Argyll.

In March 1647 new instructions for the Scottish commissioners in London added a new monarchist tone to their demands, seeking the return of the king, who need not swear to the covenant, simply assent to it. Other familiar demands on parliament remained, like the need to preserve and strengthen the union, and for English ships to prevent further Irish crossings and protect Scottish trade on the east coast, the latter reiterated a few days later. The rationale was that defence would provide for the security of both kingdoms, and the Irish and Royalists harassing Scottish ships were English subjects. The estates had disconnected naval defence from any notion it was a trade for Scottish soldiers in England, but parliament was more interested in completing the withdrawal of Scottish forces than providing support, voting to end all payment to the army in Ulster.