The Central British Fund (CBF) put together a large team of people to look after the Boys.
The Boys were teenage and child-Holocaust survivors, who were brought to the UK after the war for rest and rehabilitation.
The British government offered 1,000 visas to bring the Boys to the UK but the caveat was that the CBF were responsible for their care and would pay all the expenses.
Marx was born in 1886 in Germany. He was a teacher, and he and his wife Roza ran the Israelite Orphage for Jewish children in Frankfurt.
Marx helped to save 1,000 children during the Kindertransport and accompanied many transports to the UK, Switzerland and France. He came to the UK with the last Kindertransport from Frankfurt at the end of August 1939. He later became the warden of the Northampton hostel, looking after the members of the Boys there.
His wife was taken with the remaining orphans to the Theresienstadt Ghetto in Czechoslovakia in 1942. She died in the Holocaust.
He later remarried Gitta Goldsmith and they had two children, Moses and Esther.
Marx died in 1968 in New York.