King George's outburst is a reference to the recurring bouts of mental illness that he suffered in his later years. Diagnoses ranging from porphyria to bipolar disorder have been suggested, but the precise nature of his illness has never been determined.
The Duke and I is the name of the first book in the Bridgerton series on which this season is based.
The scene when Daphne and Simon plead their case to the Queen so they can get married quickly had to be shot very quickly because the real life royal family was about to use the area they were filming in.
A bride in the Georgian era would not wear white as Daphne does. It was Queen Victoria who broke with tradition in choosing a white wedding gown in 1840 (in order to appear clearly in the black and white photographs new to newspapers at the time) that made white wedding gowns fashionable. During this period a wedding dress might be of floral tones or golden fabric.
Emma Naomi and Ben Miller both appeared in all 6 episodes made to date of the UK version of Professor T