They returned to Bucharest after the war in 1919. This time, his father went into the box manufacturing business. It was at his factory that Steinberg gained a familiarity with various materials such as coloured and embossed papers, stamps and type, that would all feature later in his art. He was an academic student, but his school years were unhappy as he faced anti-Semitic bullying. In the lead up to the Second World War, while he was studying Sociology and Psychology at the University of Bucharest, anti-Semitic views became increasingly prevalent. In 1933 he moved to continue his studies in architecture in Milan at the Regio Politecnico. Here he became deeply engaged in drawing and began working for Italian newspapers that specialised in humour and satire. However, this time of progress and independence came to an end when Mussolini barred Jews from having skilled professions. 

 

Despite this, Steinberg remained in Milan long enough to earn his architectural degree but at the time he was planning on seeking refuge in another country. He decided to leave Europe and found himself in the Dominican Republic where he spent a year until he received a US visa. Eventually, Steinberg arrived in Manhattan in 1942. He began doing freelance work for The New Yorker, Mademoiselle, PM and other publishers and by 1943 he had officially become an American citizen. 

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 'The life of the creative man is lead, directed and controlled by boredom. Avoiding boredom is one of our most important purposes.'

 

Steinberg was an ensign in the US naval reserve during the Second World War and in May 1943, he was shipped out to China where he spent six months. He also went to North Africa and Italy. During this time, Steinberg was sending The New Yorker packets of drawings, mostly depictions of off-duty military life overseas. These were published in 1944-1945. After returning from his naval duties, Steinberg married a fellow Romanian artist named Hedda Sterne. It was through Sterne that he met other émigré artists such as Marcel Duchamp, Piet Mondrian and Andre Breton. He also formed enduring friendships with fellow American artists, Alexander Calder and Mark Rothko. 

 

From 1945 onwards, his success spiked as more of his work was published and thousands of prints were sold. His work became very recognisable and popular in New York and he showed in many exhibitions, most significantly the Betty Parsons and Sidney Janis galleries, who would go on to exhibit his work for a further 25 years. Continuing a career for over six decades, Steinberg made more than 1,200 works for The New Yorker alone. His other works included intricate stage sets, photographs, and large murals.