Hans Erni served an apprenticeship as a draughtsman in an architect’s office, from 1924 until 1927. He later studied at the Kunst-gewerbeschule, Lucerne, from 1927 until 1928, and spent the next few years first in Paris at the Académie Julian, and then in Berlin at the Hochschule für Bildende Künste. After four years travelling around Europe, he returned to Switzerland and designed murals for the Swiss National Exhibition in 1939 and the Swiss Industries Fair in 1945 as well as for various well-known institutions such as the Royal Institute of British Architects in London.  He also illustrated a large number of books and designed many posters.