Graham, John T. Theory of History in Ortega y Gasset: “The Dawn of Historical Reason.” Columbia: University of Missouri Press, 1997. This is a clear look at Ortega’s theory of history.
Gray, Rockwell. The Imperative of Modernity: An Intellectual Biography of José Ortega y Gasset. Berkeley: University of California Press, 1989. An extensive intellectual biography of José Ortega y Gasset that shows the development of his thought in all his major works. It places him in the history of international modernism at the turn of the twentieth century and considers his reaction to Spain’s cultural isolation.
Oimette, Victor. José Ortega y Gasset. Boston: G. K. Hall, 1982. A study of the development of Ortega’s thought against the social and political background of Spain in the first half of the twentieth century. It makes a good introduction to Ortega’s philosophy.
Silver, Philip W. Ortega as Phenomenologist: The Genesis of “Meditations on Quixote.” New York: Columbia University Press, 1978. Focuses on a specific facet of Ortega’s thought that had been neglected—namely, his existential phenomenology—and describes his relationship to German philosophers, particularly Edmund Husserl.
Tuttle, Howard N. The Crowd Is Untruth: The Existential Critique of Mass Society in the Thought of Kierkegaard, Nietzsche, Heidegger, and Ortega y Gasset. New York: Peter Lang, 1996. An examination of the thought of Ortega and others.