It's gratifying to see Oswald Veblen being more widely recognized on the internet for his contributions to American mathematics. There are still many tellings of history in which Veblen remains hidden, however. Meeting a retired Princeton-based physicist/violinist recently, I naturally thought of Einstein and told him I was researching Oswald Veblen's influence in bringing Einstein to Princeton. He said emphatically that it was the Bambergers who brought Einstein instead, through their funding of the Institute for Advanced Study. He then mentioned Richard Courant, and gave credit to New York University for bringing this great jewish mathematician to America after he was displaced from Gottingen by the Nazis.
But behind both of these stories of brilliant and impactful immigration is Oswald Veblen, who was quietly instrumental in bringing many displaced mathematicians and physicists to America. A succinct, attractively rendered telling of the story, called "Collaboration and Companionship," repeatedly mentions Veblen's involvement in bringing Einstein, Hermann Weyl, Emmy Noether, John von Neumann, Kurt Godel, and Richard Courant to the U.S.
That webpage links to another entitled "Towering Figures," in which brief stories are told of four "key individuals in pioneering and continuing the growth of the American Mathematical community": J.J. Sylvester, Felix Klein, E.H. Moore, and Oswald Veblen.
Veblen had a connection to each of the three who preceded him. His father, Andrew, would surely have studied with J.J. Sylvester at Johns Hopkins before moving to the University of Iowa in 1883 to teach physics and math--the same year Sylvester returned to Europe. And surely his father would have taken a 13 year old Oswald to hear Felix Klein speak in 1893 at the International Mathematical Congress held as part of the Chicago World's Fair. Oswald went on to study with E. H. Moore in Chicago, before moving to Princeton.
A couple asides: Biographies of Sylvester and Klein mention their work to encourage women to pursue careers in mathematics, as did Veblen.
On a more autobiographical note, I expect the Veblens would also have witnessed the 40 inch refracting telescope on display at the 1893 Chicago World's Fair. When I was growing up 70 years later, my father, W. Albert Hiltner, was director of Yerkes Observatory, where that largest of refracting telescopes still functions beneath the big dome. The Collaboration and Companionship story also describes how the Manhattan Project convinced President Hutchins of the University of Chicago to "throw massive resources into the reorganization" of the physics and math departments near the end of World War II. That funding and resources may be why I grew up where I did, as my father was hired by the U. of Chicago astronomy department around that time.