Born in Ulm, Einstein was a German citizen from birth. As he grew older, Einstein's pacifism often clashed with the German Empire's militant views at the time. About the book: https://www.amazon.com/gp/product/0312288565/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0312288565&linkCode=as2&tag=tra0c7-20&linkId=e979b817f4e8d0d7f463d2b86de10c71
At the age of 17, Einstein renounced his German citizenship and moved to Switzerland to attend college. The loss of Einstein's citizenship allowed him to avoid service in the military, which suited his pacifist views. In response to a Manifesto of the Ninety-Three signed by 93 leading German intellectuals including Max Planck in support of the German war effort, Einstein and three others wrote a counter-manifesto. Einstein accepted a position at the University of Berlin in 1914, returning to Germany where he spent his time during the rest of World War I. Einstein also reacquired his German citizenship. In the years after the war, Einstein was very vocal in his support for Germany. In 1918, Einstein was one of the founding members of the German Democratic Party. In 1921, Einstein refused to attend the third Solvay Congress in Belgium, as his German compatriots were excluded. In 1922, Einstein joined a committee sponsored by the League of Nations, but quickly left when the League refused to act on France's occupation of the Ruhr in 1923. As a member of the German League of Human Rights, Einstein worked hard to repair relations between Germany and France.
Einstein moved to the United States in December 1932, where he worked at the California Institute of Technology in Pasadena, California, and lectured at Abraham Flexner's newly founded Institute for Advanced Study in Princeton, New Jersey. Einstein renounced his German citizenship in 1933 due to the rise of Adolf Hitler and the Nazi Party.
During the 1930s and into World War II, Einstein wrote affidavits recommending United States visas for European Jews who were trying to flee persecution and lobbied for looser immigration rules. He raised money for Zionist organizations and was, in part, responsible for the 1933 formation of the International Rescue Committee,
In Germany, Deutsche Physik activists published pamphlets and even textbooks denigrating Einstein. Nobel laureates Philipp Lenard and Johannes Stark led a campaign to eliminate Einstein's work from the German lexicon as unacceptable "Jewish physics" (Jüdische Physik). Instructors who taught his theories were blacklisted, including Nobel laureate Werner Heisenberg, who had debated quantum probability with Bohr and Einstein. Philipp Lenard claimed that the mass–energy equivalence formula needed to be credited to Friedrich Hasenöhrl to make it an Aryan creation. A man convicted of inciting others to kill Einstein was fined a mere six dollars.
Albert Einstein was widely known during his lifetime for his work with the theory of relativity and physics in general. His political opinions were of public interest through the middle of the 20th century due to his fame and involvement in political, humanitarian and academic projects around the world. He was often called upon to give judgments and opinions on matters often unrelated to theoretical physics or mathematics.