If Dauphin Charles (VII) dies just before his father King Charles VI in October 1422 and Henry V of England is already dead as in OTL, the English armies in France will be under the new regent for the part of the kingdom recognising England's Henry VI as heir, ie Duke John of Bedford. But he is in no position to fight a new French Valois challenger for control of the late Dauphin's lands yet, as his position in England is precarious thanks to the ambitions of the head of the regency council there, his and Henry's youngest brother Humphrey of Gloucester. Humphrey wants full royal powers as regent of England but the majority of the regency council there, led by the brothers' uncle Bishop Henry Beaufort, are resisting this - and H is less than reliable as an ally for Bedford and is unlikely to send him any English troops if he needs them to fight for the Dauphin's lands. So the power-play in the leaderless 'realm of Bourges', the Dauphin's lands, will be free from immediate English attack.
Technically, if the Orleans heir Duke Charles is ruled out as an English captive Duke Louis (III) or Anjou is heir to France as the Anjou line is next to the defunct line of Charles V and VI. The Berry line having died out, then comes Burgundy - so does Duke Philip make a play for the crown and go back on his oath to Henry V in 1420 as per the Treaty of Troyes? He managed to get the Church to annul his oaths to Henry V and VI in OTL 1435 so he could defect back to Charles VII once the latter appeared to be winning; he could do this in 1422 or 1423 too. Louis of Anjou, barely 20, is anyway in Naples seeking the crown of that kingdom from the ageing and childless Queen Joan II, and has got the worst of the struggle with her alternative heir King Alfonso of Aragon; he does not have the troops or money to come back quickly to France and launch a realistic bid for the throne. His teenage brother and heir Rene is even younger and currently away in Lorraine seeking a bride and lands there as its duke's ward.
Given Philip of Burgundy's ambitions and vast resources, he is the likeliest Valois prince to try to claim the vacant throne and send in his troops to seize the Dauphinist 'capital' and treasury, possibly as 'regent' for the absent Charles of Orleans if his initial soundings at the Dauphin's court indicate that his claiming the crown will meet overwhelming hostility. After all, the Dauphin's men stabbed Philip's father Duke John to death during a truce meeting on the bridge at Montereau in 1419, throwing Philip into an initially unwanted alliance with Henry V to get his revenge. If he takes over the Dauphinist court, he will be looking for the assassins and those behind them, and mass-executions are likely; the courtiers around the late 'Charles VII' will not want to throw themselves on Philip's mercy. Philip will probably also seek to hand over much of Charles' lands to his own allies to secure control of the region for a Burgundian loyalist courtier regime. Arguably,sooner than accept that the Bourges elite, with their Scots guards regiment and assorted routier commanders like La Hire and Orleans' half-brother the 'Bastard of Orleans'/ Dunois, would rather try to hold out on their own as a nominal regency regime for an alternative 'Charles VII' ie the captive Duke Charles of Orleans.
So we end up with an interesting multi-way battle of allegiances, that could easily turn into a messy civil war. It all depends on what Burgundy does - and if he gambles on defying the English and trying to take over the Dauphin's lands as 'King Philip VII' we could end up with the Bourges regime either breaking up or with part of its leadership having to grit their teeth and ask the English for help to save their own skins. Bedford would then be the kingmaker, with his smallish but lethal army backed up once the new regency in England is stable enough to hold a Parliament and raise money and troops - and he would be furious with Philip for violating his oaths. As he will only accept his nephew Henry VI as the legal King of France, he will try to force acceptance of this on the Bourges leadership - and logically his current hostage King James I of Scotland (only released to go home by Bedford in 1424 in OTL after being an English 'guest' since 1406) will be a crucial factor in establishing a link to the Scots commanders in the Bourges army, James' cousin John of Buchan and the earl of Douglas. So does Bedford agree to let James go home if he can win over Buchan and Douglas, and the latter's OTL employer the Dauphin is dead and has no son so they agree. There is an uneasy English-Bourges alliance against Burgundy, and a war follows - possibly with Bedford allowing the legal heir to France in French eyes, Charles of Orleans, to help out in France so that legalists will fight for him against 'usurper' Philip of Burgundy. The Anglo-Scots-Dauphinist army might then hold Burgundy back, but it will be too weak to defeat him decisively.
So we end up with another messy temporary truce around 1426, with two 'Kings of France' in one country and no permanent solution likely?Joan of Arc has no 'legitimate king' to crown unless she and her backers support Charles of Orleans in a revolt against the English regime; and once Rene of Anjou has got the heiress and resources of Lorraine (c.1430) he can add his ambitions to the mix. Given the extra strain of the war on the resources of 'English' France (Normandy, Paris, Guienne etc) plus a cost-conscious English regency, perhaps the English position would collapse if Charles of Orleans revolted with Angevin backing, particularly once Bedford is dead (1435 as in OTL).We end up with 'Charles VII' (Orleans) as king of France, reigning to 1465 when he died in OTL, but a deep division between Orleanist France and their Burgundian rivals - who in this scenario might try to 'go it alone' as an independent kingdom. And if England is fighting Burgundy not acting as its ally in the 1420s-30s, then Duke Humphrey could be allowed by Bedford and the Church to keep his legally questionable wife, duchess Jacqueline of Holland, not divorce her, to prise Holland away from Burgundian control. If he has Holland's resources, can her defeat his OTL rivals at Henry VI's court in the 1440s and avoid ruin and arrest in 1447?
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