Unfortunately the Venice in Peril Fund is not fictitious. It is a real organisation, still struggling to save the city and its treasures from rising water levels.
The danger can be seen in the video below.
In 1620 The Mayflower sailed from Plymouth, England, carrying a small group of Puritans seeking to practise their religion freely in New World. They were among the first Europeans to settle in America, founding a colony, 'New England', in the north-east. Puritans were renowned for the strictness of their religion, and disapproved strongly of Roman Catholicism.
While some individual Catholic priests, including the late Pope John-Paul II, are credited with having helped Jews escape the Nazis, the relationship of the Roman Catholic Church, as an institution, to Nazism was complicated and open to different interpretations.
An allusion to the The Merchant of Venice by William Shakespeare. Shylock is Jewish, and his traditional cloak suffers for it:
Signior Antonio, many a time and oft
In the Rialto you have rated me
About my moneys and my usances:
Still have I borne it with a patient shrug,
For sufferance is the badge of all our tribe.
You call me misbeliever, cut-throat dog,
And spit upon my Jewish gaberdine,
And all for use of that which is mine own.
Act 1, Scene 3
The Chiesa dei Santi Apostoli di Cristi is a seventh century church in the Cannaregio district of Venice. It's no. 10 on the map at the back of the book.
Sarah's appartment is marked 13 on the map at the back of the book. It is in the Campo Gheto Novissimo, one of three areas to which Jews were confined under the Republic of Venice. Buildings rose high because of the confined space.There's a good photo here.
The prophet Zarathustra (also known as Zoroaster) founded Zoroastrianism around 3,500 years ago , and between 600 BCE and 650 CE, it was the official religion of Persia (Iran). It posits an ongoing battle between good and evil and encourages its adherents in 'good thoughts, good words and good deeds.' Fire is sacred, representing the light and wisdom of God (Ahura Mazda, the Wise Lord). It seems that Zoroastrianism has strongly influenced both Judaism and Christianity, and many scholars now believe that the three magi of the Christian gospel nativity story were Zoroastrian priests. The author believes that the story of Tobias and the angel derives from Zoroastrianism, one reason for this being the presence of the dog. Dogs were generally regarded as unclean in Judaism, but in Zoroastrianism they were important, and were considered to lead the soul, at death, to the other world. The author has written about Zoroastrianism and the Book of Tobit in Author's Note at the end of the novel. (p.340-342)
The Book of Enoch is an ancient scripture referred to in the canonical (authorised) scriptures of both Judaism and Christianity, but not included in the canon of either.
During the ongoing hostilities between Pisa and Genoa in 13th century Italy, Count Ugolino allegedly betrayed the archbishop of Pisa, who then betrayed him to the mob, resulting in his being locked in a tower with his two sons and two grandsons, and left to die of starvation. According to Dante, Ugolino was forced to eat the dead bodies of his children, though this has not been substantiated by modern forensic investigation. On his tour of Hell, guided by the poet Virgil, Dante meets Ugolino and the archbishop in the eighth circle, reserved for those guilty of betraying kith and kin. They are trapped together in ice, Ugolino eternally torturing the archbishop by gnawing at his neck, presumably from eternal insatiable hunger.
The painting is by William Blake.