Why is it called John Walker & Sons King George V?
It commemorates the Royal Warrant that King George V granted to John Walker & Sons on 1 January 1934, appointing the company a supplier of Scotch whisky to the Royal Household. It was the firm's first Royal Warrant. The whisky is built to match the occasion: every component comes from a distillery that was operating during that king's reign.
Does King George V contain Port Ellen whisky?
Yes. John Walker & Sons states that the blend includes casks from Port Ellen, the Islay distillery that closed in 1983 and whose stock cannot be replaced. Port Ellen is where the coastal smoke in the finish comes from, and it is the component the blend is most often sought out for, since Port Ellen bottlings on their own are both scarce and expensive.
Which distilleries are in John Walker & Sons King George V?
Only one is named publicly: Port Ellen. What John Walker & Sons does state is the rule rather than the recipe — every whisky in the blend comes from a distillery that was operating during King George V's reign, between 1910 and 1936, and several of those distilleries have since closed. The full component list has not been published, so any complete list circulating elsewhere is not from the producer.