The First World War was very recent history at this point in the novel. All the colonies and dominions of the British Empire, like Canada, were automatically drawn into the conflict when Britain declared war on Germany in 1914. 67,000 Canadian soldiers lost their lives.
An M.C., or Military Cross, is a military decoration that was created in 1914. In the period referred to here, it was awarded to commissioned and warrant officers in the British Army, for acts of exemplary gallantry. It could also, at that time, be awarded to officers of British Empire dominions.
A.D.C. stands for aide-de-camp, an officer who acts as an assistant and secretary to a high-ranking member of the military, such as a general.
The character Ma Mayfield is based on a real-life Irish-born night club owner called Kate Meyrick (1875-1933).
Meyrick was involved in the running of several night clubs in London during the 1920s, including one at 43 Gerrard Street, Soho which was the model for the Old Hundredth.
Mrs Meyrick crossed swords with the law on many occasions, and served five prison sentences for offences relating to her night club ownership.
Sink Street does not exist, but Mrs. Meyrick's night-club at 43 Gerrard Street, Soho was not far from Leicester Square. It is now a thriving part of London's Chinatown.
Trumper's is a men's barber shop, established by George Trumper in Curzon Street, Mayfair, in 1875.
Today it has two branches: the original one in Curzon Street; and a second one in Duke of York Street, St. James's.
The Star was a London evening newspaper; it was founded in 1888, and ceased publication in 1960.
Bow Street Magistrates' Court has existed at various sites on Bow Street in Central London since 1740.
The most recent site of the Magistrates' Court, and the building in which Sebastian's case would have been heard, ceased functioning as a courtroom in 2006.
Various famous defendants, including Oscar Wilde, have appeared at Bow Street prior to pleading their cases before higher courts.
Gunter's at 7-8 Berkeley Square began life as a confectionary shop in 1757, trading under the name of The Pot and Pine Apple.
During the 19th and 20th centuries it functioned as a tea-shop, serving light meals and specialising in ices and sorbets. It is still in existence today.
Berkeley Square is a highly desirable residential area in Mayfair, London.
The Dominicans are a Catholic religious order founded by St. Dominic in the early 13th Century.
Jacques Maritain (1882-1973) was a French philosopher who converted to Catholicism in 1906.
Georg Wilhelm Friedrich Hegel (1770-1831) was a German philosopher whose thinking had a significant influence on subsequent philosophical and ideological developments, including Marxism.
Charlus is an aristocratic, decadent homosexual character in Marcel Proust's seven volume, semi-autobiographical novel In Search of Lost Time (also translated as Remembrance of Things Past).
His full name is Baron Palamède de Charlus, and he appears for the first time in the second volume, Within a Budding Grove (1919).
The character is said to be based on the French symbolist poet and art critic Robert, comte de Montesquiou-Fezensac (1855-1921).
Jesus is reputed to have responded to a rich young man who asked him how to achieve eternal life: It is easier for a camel to go through the eye of a needle than for a rich man to enter the kingdom of God. (Matthew 19:24)
Slightly different versions of the same statement appear in Luke 18:25 and in Mark 10:25.
It is now believed that camel may be a mis-translation, and that the sentence should read: It is easier for a rope to go through the eye of a needle than for a rich man to enter the kingdom of God.
Father Brown is a character who appears in 52 short stories by G.K. Chesterton. The stories were published in five volumes between 1911 and 1935. The Wisdom of Father Brown (1914) is the second volume, containing 12 stories.
Father Brown was based on a real-life Catholic priest, Father John O'Connor (1870-1952), who was involved in Chesterton's conversion to Catholicism.