Why did Engel leave German?

Engel left Germany for several reasons, primarily due to political and social upheaval. The rise of the Nazi regime and its oppressive policies against socialists and communists created an unsafe environment for individuals like Engel, who opposed such ideologies. Additionally, he sought greater opportunities for his work and ideas in a more open and accepting environment. Engel's departure was part of a broader trend of intellectuals fleeing oppressive regimes during that period.