He later studied German and English literature at the Friedrich Wilhelm University in Berlin in the years 1921–1924, but did not graduate.

[1] As a leading member of the Communist Party, Einar was one of the main proponents in Iceland behind the popular front line, promoted by the Comintern as a means to resist the growth of fascism during the second half of the 1930s.

[1] As part of his political activity, Einar was also the editor of several left-wing newspapers, including Þjóðviljinn in the years 1936–1946.

During the Allied occupation of Iceland, Þjóðviljinn was accused of spreading propaganda against the British Army.

As a result, Einar was arrested by the British in April 1941 and transferred to London, where he was imprisoned in HM Prison Brixton for several months.