Ridley Haim Herschell (7 April 1807 – 14 April 1864) was a Polish-born British minister who converted from Judaism to evangelical Christianity. He was a founder of the British Society for the Propagation of the Gospel Among the Jews (1842) and of the Evangelical Alliance (1845),
Herschell was born in the city of Strzelno in the Duchy of Warsaw, a French client state in Poland that had previously been under Prussian control. His parents were pious Polish Jews and Haim Herschell decided at a very early age that he wanted to be a rabbi. He left home and studied under various teachers. Later, encouraged by his parents, he moved to Berlin to study literature and lived a decadent life, "like a Christian". He visited England for the first time on vacation but returned to Berlin in order to finish his studies before moving finally to London via Paris.
In France he experienced a dramatic religious conversion to Christianity and struggled with his Jewish background. He sought help from Roman Catholic clergy, but eventually turned to English evangelical contacts he had discovered in Paris through a mysterious letter of introduction he had been given before his conversion. Reconciled with his Jewish roots, but not his family, he left for England,
He entered an institution for converted Jews in the East End of London and was baptized by Charles Blomfield, the Bishop of London in 1830, sponsored by high-society evangelical Christians, He married Helen Skirving Mowbray, a woman ten years older than himself from Leith whom he met apparently by a chance introduction in London. They had a shared interest in the fashionable Scottish preacher Edward Irving. She had taken a deep interest in Judaism and the restoration of Israel and had already learned Hebrew. They were both ostracized by their families, moved to the poor districts of Woolwich and Camden Town and experienced hard times in spite of their upper class connections. They had the first of five children, two of whom would die young,