In For Want of a Nail, Sobel shows the American Revolution ending in June 1778 with the Continental Congress agreeing to return the Thirteen States to British rule. And then ...
That's basically it. The next thing you know, almost all the American armies have surrendered to the British, and the Thirteen Colonies are under martial law while everybody waits for Parliament to come up with a permanent settlement. How did thirteen separate revolutionary governments each decide to surrender power and accept subordination? We never find out.
Clearly, this is a matter that needs explaining in my sequel to Sobel, Scorpions in a Bottle. This is what I came up with:
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(this section carries on from the Carlisle Commission section)
With the Rebellion at an end, and the American colonies once more restored to British rule, Galloway held that the Congress had completed its task, and adjourned the body. As direct representatives of the North ministry, the members of the Carlisle Commission found themselves acting as a de facto government for the colonies. The commissioners established themselves in Philadelphia, and in consultation with General Howe, directed the restoration of the ministry’s authority. 
Reconciliationist regimes had been established in the Southern colonies, including Maryland and Delaware. In the middle colonies of Pennsylvania, New Jersey, and New York, the British Army had succeeded in establishing civil authority in the areas they controlled. However, the story was a different one in the New England colonies, where the Rebellion had begun, and where opposition to the return to British rule was strongest.
Burgoyne’s victory at Saratoga-Albany had broken the spirit of the New England militia serving under Gates. These men had returned to their farms and villages, bringing with them tales of Gates’ incompetence and the fecklessness of the Congress. Benedict Arnold, probably the most able rebel military commander in New England, might have been able to rally the New England rebels to continue their resistance had he been able. Arnold, however, had suffered a serious injury at the Battle of Freeman’s Farm, and was recuperating in isolation at his home in Connecticut. With him gone, there was nobody in a position to counter the growing sense of despair among the New England rebels. 
At the behest of Galloway and the Carlisle Commission, Dickinson agreed to serve as an envoy to the rebel government in Boston. Dickinson found the city in turmoil, as mobs championing different rebel factions fought in the streets. The city’s leading merchants, fearing the loss of all order, agreed to Dickinson’s proposal for a regiment of British soldiers to be stationed in the city.  The Carlisle Commission assigned Howe himself to the command, and on October 17, 1778, two and a half years after their withdrawal, the British Army returned to Boston. Once order had been restored, Howe appointed Elbridge Gerry, by now a leading Massachusetts reconciliationist, as head of the colonial government.  Over the course of the next year, Howe was able to use similar measures to bring the other three New England colonies under his authority. With Howe in control of New England, Burgoyne in charge of the middle colonies, and Clinton in the South, the era of the Four Viceroys had begun. 
1. Henderson Bundy. The Carlisle Commission (New York, 2005), pp. 78-95.
2. Bamford Parkes. Benedict Arnold: The Rebel Genius (New York, 1965), pp. 217-25.
3. Lord Henry Hawkes. Peace and Victory: The Last Stage of the American Rebellion (London, 1884), pp. 623-35.
4. Robert MacKreith. Lord Howe and the Rebellion (New York, 1965), pp. 303-14.
5. Sir Guy Carleton, Governor of Quebec, is considered the fourth Viceroy, although he did not share in the task of pacification of the rebellious colonies.