War and Peace is epic in scope, and includes a number of panoramic battle scenes describing famous battles from the Napoleonic Wars in Russia and Eastern Europe. It is this sort of scene that Henry and Julian are thinking of here.
Tyrian purple is a highly prized ancient dye which comes from sea snails called murex, or Bolinus brandaris. It was first produced by the ancient sea-trading civilisation, the Phonecians ('purple people' in Greek). The dye was so expensive it became reserved by sumptuary laws for use by the emperors of Rome - hence its alternative name, 'imperial purple'.
Tartt is arguably at her weakest in this minor sub-plot. The fictional 'Isrami' government belongs to a Middle-Eastern country which, if this detail concerning the heritage of its crown princess is taken literally, would coincide geographically with modern Iraq. Its history - a monarchy overthrown by an Islamic revolution - is more like that of Iran.
In the Old Testament, the Tower of Babel was built several generations after the Great Flood, when humanity was undivided, and spoke a common language. It was designed to reach up to Heaven. When God realised this he was offended, and scattered the people and separated their speech into many different languages, driving them apart so that they would never be able to achieve such a heretically ambitious bit of architecture.
The Tower of Babel has long been identified with the Etemenanki, a large ziggurat in Babylon (modern Iraq). Dedicated to Marduk, it stood seven stories high, until it was demolished by Alexander the Great in the third century B.C.
Philip K. Dick (1928-1982) was an American writer known for his science fiction stories and novels, such as Do Androids Dream of Electric Sheep? and A Scanner Darkly. His work often deals with issues of paranoia, drug abuse and mental illness. As well as influencing many contemporary writers, his work also influenced modern philsophy, and is considered to have foreshadowed the development of post-modernism.
The Buffalo Springfield was an American rock band whose lineup included Neil Young and Stephen Stills, later of Crosby, Stills, Nash and Young. They formed in 1966 but lasted only two years, during which time their best-known song was 'For What It's Worth'. The group is now best remembered for launching the musical careers of Young and Stills.
Simon and Garfunkel are a hugely successful American duo of singer-songwriters Paul Simon and Art Garfunkel. Forming in 1957, the duo rose to fame in 1965 after their song The Sounds of Silence became a hit. Their success was consolidated when their music featured in the 1967 film The Graduate. Although the duo have broken up twice, they keep reuniting; however, their most recent plans for a tour have been put on hold as Art Garfunkel recovers from damaging his vocal cords.