Ernst Michaelis was born in Berlin in 1926. His family were liberal Jews with a strong sense of German national identity. His father Walther Michaelis (1880-1942) was a judge serving in the Amtsgericht. In 1933 Walther was appointed president of the court in Charlottenburg, Berlin. However the Nazi rise to power prevented him from taking on the position, and he was removed from office. He devoted himself to Jewish institutions supporting the victims of Nazi persecution, setting up two schools – the Joseph-Lehman School and the Holdheim School – for Jewish children and helping people escape the country. Ernst studied at these schools; at the Holdheim School, he was friends with Peter Schiff, who moved to Amsterdam and is mentioned in Anne Frank’s diary. As a boy, Ernst had a passion for DIY projects. Ernst’s mother Teresina (Resi) Michaelis née Pincus (1892-1942) devoted herself to helping the blind. Ernst had an older brother – Werner Martin Michaelis (1923-1942). Ernst’s parents remained in Germany to support members of the Jewish community who could not escape. Werner had been due to leave the country but never made it. Ernst's family were deported to Riga in October 1942, where they were shot in woods nearby.

Ernst arrived in Britain on a Kindertransport on 10 August 1939. His journey was organised by two Quakers – Elisabeth Landman in Germany and Evelyn Atkinson in England. Mrs Atkinson acted as Ernst’s guarantor and organised a place for him at St Mary’s boarding school, which catered primarily for children with special needs; however it also took in economically disadvantaged children, including refugees. He later became a governor and trustee of the school; a learning suite was named after him in 2003. After a year, Ernst moved on to the private Bryanston School; again, Mrs Atkinson organised his place there. He left in 1945 and got a job in a factory where he trained as a toolmaker; he qualified as a Chartered Mechanical Engineer in evening classes. He became a specialist in metal forming machine tools and was director of Pearson Panke, which supplies automotive and aerospace machinery. He only retired in 2014. He met his wife Ann (1939-2005) while she was a student teacher at St Mary’s; they married in 1960 and had two children. Ernst was the only member of his immediate family to escape Germany and survive the Holocaust. He died in 2020.