How would historic monarchs have pronounced their own names?

Many of the names of the kings of England were Norman French in origin. Take Henry. I assume this would originally have been pronounced like the French, with a dropping of the initial H. But by the time of Henry VIII, Early Mordern English would have started to kick in. Would He have pronounced his name with the H? If so, when would the change have come about?

Were their names much different from how we write them in the modern, e.g. Elizabeth or something like Elisabeth? I'm guessing someone like Estienne de Blois would have been given the name Stephen only much later. Was John actually Jean or something similar? Was George a name introduced to England with the Georgian kings? Our modern pronunciation seems quite archaic, yet very different from how I presume George I would have called himself (/gei org/).

More recent monarchs have taken to assuming a regal name different from their given names. When and how did this practice begin?

Would appreciate any fun info you can spare!