At the University of Marburg, she studied philosophy with Martin Heidegger, with whom she embarked on a long, stormy and romantic relationship for which she was later criticized because of Heidegger's support for the Nazi party while he was rector of Freiburg University.
In the wake of one of their breakups, Arendt moved to Heidelberg, where she wrote her dissertation on the concept of love in the thought of Saint Augustine, under the existentialist philosopher-psychologist Karl Jaspers.
She married Günther Stern, later known as Günther Anders, in 1929 in Berlin (they divorced in 1937).
The dissertation was published the same year, but Arendt was prevented from habilitating, a prerequisite for teaching in German universities, because she was Jewish. She worked for some time researching anti-Semitism before being interrogated by the Gestapo, and thereupon fled Germany for Paris. Here she met and befriended the literary critic and Marxist philosopher Walter Benjamin, her first husband's cousin. While in France, Arendt worked to support and aid Jewish refugees. She was imprisoned in Camp Gurs but was able to escape after a couple of weeks.
However, with the German military occupation of northern France during World War II, and the deportation of Jews to Nazi concentration camps, even by the Vichy collaborator regime in the unoccupied south, Arendt was forced to flee France. In 1940, she married the German poet and Marxist philosopher Heinrich Blücher, by then a former Communist Party member.
In 1941, Arendt escaped with her husband and her mother to the United States with the assistance of the American diplomat Hiram Bingham IV, who illegally issued visas to her and around 2500 other Jewish refugees. She then became active in the German-Jewish community in New York. In 1941-1945, she wrote a column for the German-language Jewish newspaper, Der Aufbau. From 1944, she directed research for the Commission of European Jewish Cultural Reconstruction and traveled frequently to Germany in this capacity.
After World War II she returned to Germany and worked for Youth Aliyah. Later she resumed relations with Heidegger, and testified on his behalf in a German denazification hearing. She became a close friend of Jaspers and his Jewish wife, developing a deep intellectual friendship with him and began corresponding with Mary McCarthy. In 1950, she became a naturalized citizen of the United States. Arendt served as a visiting scholar at the University of California, Berkeley, Princeton University and Northwestern University. She also served as a professor on the Committee on Social Thought at the University of Chicago, as well as at The New School in New York City, and served as a fellow at Yale University and Wesleyan University. In 1959, she became the first woman appointed to a full professorship at Princeton.
Arendt was instrumental in the creation of Structured Liberal Education (SLE) at Stanford University. She wrote a letter to the then president of Stanford University to convince the university to enact Mark Mancall's vision of a residentially-based humanities program.
Arendt theorizes freedom as public and associative, drawing on examples from the Greek "polis", American townships, the Paris Commune, and the civil rights movements of the 1960s (among others) to illustrate this conception of freedom.
Another key concept in her work is "natality", the capacity to bring something new into the world, such as the founding of a government that endures.
Her first major book was The Origins of Totalitarianism (1951), which traced the roots of Stalinist Communism and Nazism in both anti-Semitism and imperialism. The book was controversial because it suggested an essential identity between the two phenomena, which can be considered as completely separated in both origins and nature.
Arguably her most influential work, The Human Condition (1958) distinguishes between labour, work, and action, and explores the implications of these distinctions. Her theory of political action is extensively developed in this work.
Another of her important books is the collection of essays Men in Dark Times. These intellectual biographies provide insight into the lives of some of the creative and moral figures of the 20th century, among them Walter Benjamin, Karl Jaspers, Rosa Luxemburg, Hermann Broch, Pope John XXIII, and Isak Dinesen.
In her reporting of the Eichmann trial for The New Yorker, which evolved into Eichmann in Jerusalem: A Report on the Banality of Evil (1963), she coined the phrase "the banality of evil" to describe Eichmann. She raised the question of whether evil is radical or simply a function of banality—the tendency of ordinary people to obey orders and conform to mass opinion without critically thinking about the results of their action or inaction. Arendt was extremely critical of the way that Israel conducted the trial. She was also critical of the way that many Jewish leaders acted during the Holocaust, which caused an enormous controversy and resulted in a great deal of animosity directed toward Arendt within the Jewish community. Her friend Gershom Scholem, a major scholar of Jewish Mysticism, broke off relations with her. She was criticized by many Jewish public figures for her coldness and lack of sympathy for the victims of the Shoah. Her book has only recently been translated into Hebrew. Arendt ended the book by endorsing the execution of Eichmann, writing:
Arendt published another book in the same year that was controversial in its own right: On Revolution, a study of the two most famous revolutions of the 18th century. Arendt went against the grain of Marxist and leftist thought by contending that the American Revolution was a successful revolution while the French Revolution was not. Some saw in this argument a post-Holocaust anti-French sentiment. Nevertheless, it echoed that of Edmund Burke. Arendt also argued that the revolutionary spirit had not been preserved in America because the majority of people had no role to play in politics other than voting. She admired Thomas Jefferson's idea of dividing the counties into townships, similar to the soviets that appeared during the Russian Revolution. Arendt's interest in such a "council system", which she saw as the only alternative to the state, continued all her life.
Her posthumous book, The Life of the Mind (1978, edited by Mary McCarthy), was incomplete at her death. Stemming from her Gifford Lectures at the University of Aberdeen in Scotland, this book focuses on the mental faculties of thinking and willing (in a sense moving beyond her previous work concerning the vita activa). In her discussion of thinking, she focuses mainly on Socrates and his notion of thinking as a solitary dialogue between me and myself. This appropriation of Socrates leads her to introduce novel concepts of conscience (which gives no positive prescriptions, but instead tells me what I cannot do if I would remain friends with myself when I re-enter the two-in-one of thought where I must render an account of my actions to myself) and morality (an entirely negative enterprise concerned with non-participation in certain actions for the sake of remaining friends with one's self). In her volume on Willing, Arendt, relying heavily on Augustine's notion of the will, discusses the will as an absolutely free mental faculty that makes new beginnings possible. In the third volume, Arendt was planning to engage the faculty of judgment by appropriating Kant's Critique of Judgment, however she did not live to write it. Nevertheless, although we will never fully understand her notion of judging, Arendt did leave us with manuscripts ("Thinking and Moral Considerations", "Some Questions on Moral Philosophy,") and lectures (Lectures on Kant's Political Philosophy ) concerning her thoughts on this mental faculty. The first two articles were edited and published by Jerome Kohn, who was an assistant of Arendt and is a director of Hannah Arendt Library, and the last was edited and published by Ronald Beiner, who was taught by Arendt and is a professor of political science at the University of Toronto. Her papers were deposited at Bard College at the Stevenson Library in 1976, and comprise approximately 4,000 books, ephemera, and pamphlets from Arendt's last apartment. The college has begun digitally archiving some of the collection, which is available at http://www.bard.edu/arendtcollection/