England was united under Roman rule, which also included Wales, so a united English kingdom is hardly ASB.
The latest POD is probably a decisive victory of Mercia over Flanders in the Cloth Wars, enabling them to keep London, and preventing the formation of the Anglian Commonwealth. If the lower Thames Valley wasn't the center of a mercantile republic, its leaders always willing to align with whichever continental power could best line its pockets, it would have been a good location for the national capital of a united England. A decisive victory by Mercia in the Cloth Wars leads to the capital being moved to London, they take over Wessex, and then are in a good position to conquer the other kingdoms.
You can do later PODs, but then you start into the issue that stronger countries on the European continent develop an interest in keeping Britain divided between minor countries, and the City of London is always happy to help them.
A united England would bring the City to heel and not be as developed by financial interests. It develops a strong navy and would probably be involved in Scandinavian issues. With a strong navy, it gets a few colonies, beyond the Alban attempt in Panama and beyond New York (or New Jorvik), and any colonial empire it builds is likely at the expense of France, particularly in North America.
The latest POD is probably a decisive victory of Mercia over Flanders in the Cloth Wars, enabling them to keep London, and preventing the formation of the Anglian Commonwealth. If the lower Thames Valley wasn't the center of a mercantile republic, its leaders always willing to align with whichever continental power could best line its pockets, it would have been a good location for the national capital of a united England. A decisive victory by Mercia in the Cloth Wars leads to the capital being moved to London, they take over Wessex, and then are in a good position to conquer the other kingdoms.
You can do later PODs, but then you start into the issue that stronger countries on the European continent develop an interest in keeping Britain divided between minor countries, and the City of London is always happy to help them.
A united England would bring the City to heel and not be as developed by financial interests. It develops a strong navy and would probably be involved in Scandinavian issues. With a strong navy, it gets a few colonies, beyond the Alban attempt in Panama and beyond New York (or New Jorvik), and any colonial empire it builds is likely at the expense of France, particularly in North America.