Albert Einstein was born in 1879 in Germany, the first child of a bourgeois Jewish couple. The young Albert displayed an early interest in science, but he was unhappy with the principles of obedience and conformity that governed his Catholic elementary school. At the age of ten, he began attending the Luitpold Gymnasium, though most of his education consisted of the study and reading he undertook on his own under the guidance of his Uncle Jakob and the young medical student and family friend Max Talmud. Talmud recommended popular science and philosophy books that put an abrupt end to the boy's short-lived but intense religious fervor, perhaps to the relief of his nonobservant parents.
When his parents moved to Italy in 1893, Einstein dropped out of school and renounced both his German citizenship and his Jewish faith. He applied to study at the Zurich Polytechnic, an advanced Swiss technical institute. However, he failed the entrance examinations and was not accepted until spending a year of preparation at a Swiss secondary school. Between 1896 and 1900, he participated in a teachers' training program at the Zurich Polytechnic, where he met his lifelong friends Marcel Grossman and Michele Angelo Besso, as well as his first wife, Mileva Maric. Following the completion of his program in 1900, Einstein went on to work as a teacher and tutor in a series of posts in Germany and Switzerland. He finally settled in Bern, Switzerland, in 1902, where he received a job as a technical expert in a patent office. In Bern, Einstein married Mileva and the couple raised two sons together.
The year 1905 has been termed Einstein's annus mirabilis, or miracle year, because it was in this year that the scientist published three of his most important papers and completed most of the work for his doctoral degree, which he received in 1906. Einstein's papers dealt with quantum theory, Brownian motion, and special relativity. In subsequent years, he expanded his theory of special relativity to account for accelerating frames of reference, so that he could then theorize that the laws of physics (including both mechanics and electrodynamics) are the same for all observers in all frames of reference. This theory, known as general relativity, was fully formulated by 1915. In 1919, scientists verified general relativity through measurements taken during a solar eclipse, and Einstein was catapulted into a position of international prominence. However, while his relativity theory won him popular fame, it was his contributions to quantum theory that won Einstein a Nobel Prize in 1922.
For most of Einstein's life, he worked as a university professor. He began at the University of Bern in 1909, but also taught at Prague and Zurich before ultimately settling at the University of Berlin and the Prussian Academy of Sciences in 1915. Although Mileva and their sons initially lived in Berlin with Albert, the couple separated shortly thereafter and in 1919 obtained an official divorce. Einstein remarried that same year, to his cousin Elsa Lowenthal, and lived with her until her death in 1936.
During the 1920s and 1930s, Einstein became increasingly active in politics and international affairs. He was a strong supporter of Zionism and traveled on a lecturing tour to the United States in 1922 to raise money on behalf of a new Hebrew University in Jerusalem. Einstein's Zionism was primarily cultural rather than nationalistic; he wanted to preserve the values of social justice and intellectual aspiration that he associated with the Jewish people. In addition to his Zionism, Einstein was also a militant pacifist during and following World War I. He was critical of nationalism and committed to the idea of a single world government without any need for armed forces. Throughout the 1920s, he participated in numerous peace campaigns and wrote articles on international peace and disarmament. However, when Hitler's National Socialist party came to power in Germany in 1933, Einstein began to rethink his rigid pacifist stance. When the Nazis began targeting him in their anti-Semitic propaganda, Einstein resigned from the Prussian Academy of Sciences and accepted a full-time position at the Institute for Advanced Study at Princeton University. Einstein departed further from his pacifism during World War II, when he actively participated in the war effort, working for the US Navy and writing a letter to President Roosevelt in 1939, in which he urged him to accelerate the nation's nuclear weaponry development. However, Einstein never advocated the dropping of the atomic bombs on Japan and worked until his death in 1955 in a campaign for international peace and nuclear disarmament.
Einstein's greatest contributions to physics were his synthesis of mechanics and electrodynamics through his relativity theory, and his challenge to Newtonian physics through his quantum theory. However, the impact of his ideas was not limited to science: Einstein's achievements influenced philosophy, art, literature, and countless other disciplines. As an individual passionate in his convictions and outspoken in his politics, Einstein transformed the image of the scientist in the twentieth century. It comes as no surprise, therefore, that TIME Magazine selected Albert Einstein as "Person of the Century," hailing him as "genius, political refugee, humanitarian, locksmith of the mysteries of the atom and the universe."