Southampton Plot

When I look at the year 1415 I see something akin to a fool's paradise with regard to alternate historians. The Council of Constance, the battle of Agincort, the conquest of Cuerta...some many events with so many long range impacts on history, all just waiting for that metaphorical monkey wrench to be tossed into the gears.

I see the most potential here:

http://en.wikipedia.org/wiki/Southampton_Plot

Postulate if you will an Edmund Mortimer with a higher political aspirations for England and far less loyalty to Henry V. From there, I have some questions.

1. Historians (those few I can find that touch on the subject) can't seem to agree on how effective the Southampton Plot would have been. Some argue that the charges for conspiracy to murder the king were trumped up to ensure the death penalty, while others think there must have been some veracity to that plot. Some say the Plot was sloppily planned and would have inevitably failed, others note how powerful the conspirators were in terms of influence and have speculated that at the least a major uprising or a war with Scotland could ensued. What holes do YOU imagine would need to be filled up for the Plot to succeed? Is it more interesting in your mind to keep Henry alive or dead?

2. A successful Southampton Plot will most certainly lead to battle, but whether that involves a full scale "war of the roses" style event or a localized siege to entrap rival claimants is more debatable. How long would you imagine the conflict would last, and who do you think would win? Does the involvement of other nations like Wales or Scotland influence the outcome?

3. Portugal has a long history of alliance with England, and henry the navigator and other Portuguese royals have a direct connection to the Lancastrian dynasty. Could a civil war in England draw a response from Portugal, especially if things go poorly for henry's brothers?

4. How will a postponement of Agincort affect any future campaigns in France?

5. How will a lack of a Henry V affect English relations with Sigismund the Holy Roman Emperor? What impact, if any, will it have on the Council of Constance.

6. Aside from Agincourt, are there any other lesser known deeds of Henry V that could significantly change history if the man isn't around to perform them? I've thought of a few, but I've yet to pour over any biographies about the man, so any more ideas will be helpful. Even a starting point to look at further details is appreciated.
 
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