It was not explicitly stated, the park which Lestat and Louis like to take the night air in, is actually Jackson Square, named after former American President Andrew Jackson. As stated, it was modeled after the Place de Vosges in Paris, used to be called the Place d'Armes, and it was the spot where the Louisiana Purchase signed. The treaty known as the Louisiana Purchase where Napoléon Bonaparte ceded all of the French territory in the United States for $15 million to President Thomas Jefferson.
Ferdinand Joseph LaMothe (AKA Ferdinand 'Jelly Roll' Morton) was a real jazz pianist from this era. His life story was adapted for the Broadway musical 'Jelly's Last Jam,' starring Gregory Hines in the lead role.
The drinking song which Lestat sang in unison with the servicemen is called "Where Do We Go From Here?" It was written by Percy Wenrich and Howard Johnson and was a popular tune in 1917 shortly following America's entry into World War I.
The First World War, also known as The Great War or the War that will End All Wars, occurred between the years 1914 to 1918. Woodrow Wilson brought the United States into the conflict in 1917. It was mostly confined to Continental Europe, and the countries within its confines had controlled the world through its colonial possessions.