I often read that when Charles VII of France got crowned in Reims it secured his claim on the french kingdom. This always got me to wounder why Henry VI simply didn't get crowned king first?
In May 1420 Charles VI and Henry V signed the Treaty of Troyes which married Henry to Charles' daughter and pronounced him as heir to the throne of France. Ultimately Henry died first (probably of dysentery) unexpectedly leaving an infant Henry VI who technically inherited the crowns of France and England. The English crown was weakened by this position and Charles VII took advantage to have himself crowned king of France.
Disputes over the inheritance of the French crown, and internal rivalry between the French nobility, framed the latter phases of the Hundred Years War. Charles VII's victories and unification of France's noble families completely undermined the English claim to the French throne in any practical sense, although it remained in principal for centuries later.