Complex sentence: When the king invites him to Sandringham, Franklin meets Winston Churchill and Jackie Fisher, and Ernest Cassel, allowing Fraser to depict some historical background about the build-up to the First World War.
Split into simpler sentences: When the king invites him to Sandringham, Franklin meets Winston Churchill, Jackie Fisher, and Ernest Cassel. This allows Fraser to depict some of the historical background of the build-up to the First World War.