[1] It is possible that at this time a house of his in London fell into the hands of the king and was afterward (1214) transferred to the Earl of Derby.
[2] He was by far the most important Jewish moneylender at Norwich in the early years of Henry II; the majority of the items in a daybook of that place now preserved at Westminster Abbey refer to his transactions.
[6] The accompanying caricature represents Isaac as three-faced, probably in allusion to the wide extent of his dealings.
He is depicted wearing a crown and observing a scene where two other Jews, Mosse Mok and a woman named Abigail, are being tortured by demons, apparently under his supervision.
The document, which was on display in the 2019 museum exhibition Jews, Money, and Myth, is said to be the world's oldest antisemitic caricature.