The Second World War, lasting from the German invasion of Poland in September 1939 to VJ Day in August 1945, only encompassed six Christmases.
Some, such as Steven Weisenburger, author of A Gravity's Rainbow Companion, have written this off as an error on Pynchon's part. However, Pynchon gets it right later when he mentions 'six years of slander, ambition and hysteria.' It is probable that the 'mistake' is an intentional device meant to convey Roger and Jessica's confusion. They are, quite literally, at sixes and sevens.
Toothpaste tubes of the 1940s were made of pewter, a valuable material worth recycling to aid the war effort.
Herbert Stanley Morrison (1888 - 1965) was a British Labour politician. He rose to prominence in the party during the 1930s, and in 1940 was made the first Minister of Supply by Winston Churchill. Shortly afterwards, he succeeded John Anderson as Home Secretary. His local experience was especially useful during the Blitz.
He was responsible for a number of unpopular decisions, such as banning the pro-soviet Daily Worker newspaper. However, he was vindicated by British victory, and the Morrison shelter was named after him.
This is a reference to the American Gold Star mothers, an organisation founded after the First World War to help mothers who had lost children in the war.
It became a tradition for families to hang a Service Flag in their window, with a star for each family member serving in the military. Those who were alive were represented by a blue star, while those who had perished were represented by a gold star.
The group still exists today, with membership open to any mother who has lost a child in service of the United States. The group is strictly non-political. On the last Sunday of September, the United States honours Gold Star Mother's Day.
There was a popular belief, after the discovery of Tutankhamun's tomb in 1922 by Howard Carter, that a curse had been unleashed to wreak revenge on those who had disturbed the pharaoh.
British novelist Marie Corelli wrote a letter to the New York World magazine quoting an obscure book that promised punishment for those who disturbed a tomb. Two weeks later, the expedition's financial backer, Lord Carnarvon, died. He had been bitten by a mosquito, and opened the bite again whilst shaving. He died of blood poisoning. Arthur Conan Doyle asserted that Lord Carnarvon had been killed by the curse, and a media frenzy ensued.
Reports emerged that after a paperweight made out of a mummy's hand and bearing an inscription promising 'fire, water and pestilence' was given to Carter's friend Sir Bruce Ingham, Ingham's house burned down, and a flood followed after the house was rebuilt.
A variety of other deaths have been attributed to the curse. However, plenty of people involved in the expedition, most notable Howard Carter himself, lived long and healthy lives. He died in March 1939, at the age of 64.