Identity and discussions thereof have become both momentous and fraught issues. This makes a figure like Hugo Marcus, whose definition of his belongings was marked by both idiosyncrasy and self-determination, all the more interesting today. Marc David Baer's biography of Hugo Marcus provides deep insight not only into Marcus's life, but also into his intellectual quests. Baer has done us all a great service by following the trail of Marcus's searches.

Hugo Marcus, a.k.a. Hamid Marcus, a.k.a. Hans Alienus, was born into a Jewish family in 1880 in what was then Posen in Prussia and is now Poznań, Poland. In 1898, after graduating from the Gymnasium, he moved to Berlin and became acquainted with Magnus Hirschfeld and his Scientific Humanitarian Committee, where Marcus also worked on occasion. He studied philosophy at the Berliner University. Hugo Marcus also became close friends with pioneering gay rights activist Kurt Hiller, and the two collaborated throughout their lives. He joined the George-Kreis, the circle around the poet Stefan George, and emigrated to Switzerland in 1939, where he died in 1966. A writer and activist, Marcus participated in diverse networks up until his death. His conversion to Islam in 1925 was only one of his many transformations. Today, we would say that Hugo Marcus was undogmatic, for he was able—effortlessly, it seemed—to move in very different circles. The estate of Hugo Marcus is today in the Central Library of Zurich. But Marcus was a very productive philosopher, writer, and activist, and those archives were only one of many sources that his biographer, Marc David Baer, had at his disposal. The wealth of material that Baer incorporates is impressive. He has been able not only to flesh out the life of this colorful character, but also to embed him in the intellectual context of his times.

Historical biographies can be understood as an attempt to grasp the relationship of the individual to society. In the biography at hand, Baer, as the title suggests, is most interested in the identities that Marcus continually (re)created for himself. The book's five chapters are entitled accordingly: “Fighting for Gay Rights,” “Queer Convert: Protestant Islam in Weimar Germany,” “A Jewish Muslim in Nazi Berlin,” “Swiss Refuge,” and, finally, “Hans Alienus: Yearning, Gay Writer.”

The theme that Baer uses to connect these aspects of Hugo Marcus's life is Marcus's passion for Johann Wolfgang von Goethe. Marcus's publications that dealt with Goethe are the subject of a significant portion of the book. Marcus published his first short story in 1900, only two years after his arrival in Berlin. Titled Das Frühlingsglück: Die Geschichte einer ersten Liebe (Spring Fortune: The Tale of a First Love), it is an exploration of homosexual desire and its meaning. Unsurprisingly, Marcus adheres to contemporary narratives extolling the superiority of male-male love. Baer's first chapter is more than just an outline of Marcus's coming of age, his dreams and desires. Baer also gives his readers an overview of queer life in Berlin and the work of Magnus Hirschfeld's Institute for Sexual Science.

In 1904, Marcus took on the topic of intergenerational love in a collection of stories, Meditationen (Meditations). Within it is found a sentence that could easily be Marcus's life motto: “Paradox has played the most important role in the history of the human spirit.” His philosophical publication, Die Philosophie des Monopluralismus: Grundzüge einer analytischen Naturphilosophie und eines ABC der Begriffe im Versuch (The Philosophy of Monopluralism: The Main Features of an Analytical Philosophy of Nature and an Attempt at an ABC of the Term) also can be read as an attempt at self-description or even, perhaps, as a confession. In it, Marcus developed the concept of monopluralism or a vision of the “unity of multiplicity” (“Einheit der Vielfalt”). Hugo Marcus's intensive exploration of this question can also be seen as a search for a justification of ambiguity and of the negation—or even transgression—of societal expectations. After all, according to Baer, Hugo Marcus led a queer life, saw himself as both German and Jewish, fought for gay rights, and converted to Islam.

Yet Baer would have done well to have shown more clearly what Marcus was writing against, and to have painted a clearer picture of the societal norms and expectations of the times. In 1929, Hugo Marcus, by then calling himself Hamid Marcus, gave a lecture at the Ahmadi mosque in Berlin. He had converted to Islam in 1925 but remained a member of Berlin's official Jewish community. His speech was given on the occasion of the two-hundredth birthday of Gotthold Ephraim Lessing. Marcus reminded his listeners that Muslims were committed to unconditional tolerance. But society, he continued, was far from realizing this tolerance. Reading this, one wonders what motivated Hugo Marcus to give this speech. Was it simply a general belief he held, or was he already railing against the changing political climate?

The chapter which deals with Marcus's life in Nazi Germany is the weakest chapter in the book, for the reader is left wanting to know more about how Marcus, who until then had demanded and received a high degree of self-determination in his life, dealt with his sudden subjection to Nazi categorizations. For not only were these categories determined by others, they were also linked to legal restrictions and violent limitations. After the November Pogrom in 1938, together with many other Jewish men, Hugo Marcus was deported to Sachsenhausen Concentration Camp. A few weeks later, he was released on the condition that he leave Germany. With the support of his imam, Mohammed Abdullah, among others, Hugo Marcus tried to obtain a Swiss visa. Finally, one week before Nazi Germany unleashed the Second World War, Marcus entered Switzerland as a political refugee. There he remained until his death in 1966. Under the pseudonym Hans Alienus, he published innumerable articles in the Zurich magazine for, in the main, male homosexuals, Der Kreis-Le Cercle. Baer conjectures that Hugo Marcus stayed in Switzerland because male-male desire remained a prosecutable offense in Germany up until 1969. However, the question should also be asked whether Marcus perhaps did not want to return to a country he had been forced to leave because of his Jewish roots.

Baer structures the chapters in a way that makes the biography more readable, but it occasionally threatens to force a linearity upon Hugo Marcus's life, leaving little room for its complexities and paradoxes. Despite the wealth of material at Baer's disposal, the figure of Hugo Marcus remains strangely nebulous. Yet this in no way detracts from the fact that Baer has written an outstanding and eminently readable biography.