King George’s Bridgerton appearances in seasons 1 and 2 are brief, and he is mentioned infrequently – partly because hes not meant to be a major character and partly because, by that point in time, he was simply too ill to appear publicly. Queen Charlotte, meanwhile, establishes George as a key character, of course. Played in Bridgerton by James Fleet, King George III is portrayed in the spin-off by Corey Mylchreest, in his early 20s. King George III’s three appearances in Bridgerton are initially only relevant because of what they reveal about Queen Charlotte.

https://screenrant.com/bridgerton-king-george-3-madness-illness-hidden-reason/