Short answers, pulled from the story.
Antonio Fernandez Carvajal led the secret Sephardic congregation that formed in London in the middle of the 17th century. The congregation held prayer-meetings at Creechurch Lane and conducted extensive trade with the Levant, East and West Indies, Canary Islands, Brazil, the Netherlands, Spain, and Portugal.
The Bevis Marks Synagogue was built in 1701 and is one of the first Jewish religious places in England since the Edict of Expulsion of 1290. It followed Creechurch Lane as the next established Jewish worship site in London.
In 1649, Johanna Cartwright and her son Ebenezer, two Baptists from Amsterdam, presented a petition to the army titled "The Petition of the Jews for the Repealing of the Act of Parliament for Their Banishment out of England". It called for the formal readmission of Jews to England.
Menasseh Ben Israel published Hope of Israel in 1650, arguing that Jewish readmission to England was a prerequisite for the coming of the Messiah. His argument held that the Messiah could not appear until Jews existed in every land on earth, and England was the only country still excluding them.
The Sephardic merchants in London provided Cromwell and his secretary John Thurloe with intelligence about Charles Stuart's activities in Holland and Spanish plans in the New World. Lucien Wolf later documented this relationship in a work titled "Cromwell's Secret Intelligencers".
The Edict of Expulsion of 1290 formally barred Jews from England. The Creechurch Lane prayer-meetings of the secret Sephardic congregation in the late 16th and 17th centuries represent the first Jewish religious activity in England since that edict, with the Bevis Marks Synagogue in 1701 continuing that renewed presence.