Silvanus Bevan III (1743-1830) was from a family of Welsh Quakers who were involved in banking, though he was born and grew up in London. His mother was Elizabeth Barclay, and the family were part of the banking group that was eventually to become Barclays Bank. He was the son of Timothy and the nephew of Silvanus Bevan of Swansea, both of whom were well known pharmacists in London. His uncle Silvanus was elected to the Royal Society in 1725.
Born in 1743, Silvanus III married Isabella Wakefield (1752-1769), from an old Quaker family in 1769, a marriage that lasted only 7 months as she died of fever. Four years later, in 1773, he married Louisa Kendall (1748-1838) who was also from a banking family. Louisa however, was not a Quaker, and because of Quaker rules at the time Silvanus III had to distance himself from the Quaker community, a move that would have weakened his ties to family and friends.
Thee couple went on to have seven sons, six of whom were baptised in London. The youngest son, Richard, was born in 1788 at their property in Swallowfield, Berkshire. They moved from there to Riddlesworth Hall in Norfolk before buying a house in Wiltshire in 1814. Silvanus III also had houses in Brighton and in Gloucester Place, London.
Some of their seven sons, including David the eldest and Richard the youngest, joined the bank while others - Frederick and George - became clergymen. Richard, like his father, was to marry twice. His first wife was Charlotte Hunter, with whom he had four daughters and a son.
Their youngest daughter, Harriet Caroline, died as a toddler in 1834, the year Richard Alexander - their only son - was born. Charlotte herself died shortly afterwards in 1835. Richard later married Sarah Dewar, who had been a long-time friend of Charlotte but there were no children from this marriage.
Two of Richard's remaining daughters (Theodosia and Elizabeth Charlotte) married clergymen. His son Richard Alexander married Laura Polhill and they had six children, one of who, Robert Polhill Bevan, went on to become a well known artist. Robert Polhill Bevan was born in No. 17 Brunswick Square, Hove.
The Bevan family may have stopped being Quakers, but they remained interested in religion, with some of them becoming clergymen and Richards daughters also marrying into the clergy. Richard Bevan himself was known to support dissenters from the established church.