Abstract. The American mathematical research community celebrated, symbolically at least, its fiftieth anniversary in 1938. Many of those fifty years had marked a period of consolidation and growth at home of programs in mathematics at institutions of higher education supportive of high-level research as well as of a corps of talented researchers capable of making seminal contributions in a variety of mathematical areas. By the middle decades of the twentieth century-the 1930s, 1940s, and 1950s-members of that community, like members of the broader American public, began increasingly to look outward beyond the national boundaries of the United States and toward a larger international arena. This paper explores the contexts within which the American mathematical research community, in general, and the American mathematician Marshall Stone, in particular, deliberately worked in the decades around mid-century to effect the transformation from a national community to one actively participating in an internationalizing mathematical world.The year 1938 was one of celebration and self-congratulation within the American mathematical research community. Fifty years earlier, four Columbia graduate students and two Columbia faculty members had met in New York City in order "to establish a mathematical society for the purpose of preserving, supplementing, and utilizing the results of their mathematical studies" [3, p. 4]. Within two decades, this extremely modest, local enterprise had grown into a national organization that supported two publications, its Bulletin started in 1891 and its Transactions first published in 1900, as well as regional sections in the midwest, on the west coast, and in the southwest [28, pp. 266-268 and 401-415]. By 1938, the leadership of that organization had recognized that the time was ripe both for chronicling its history and for showcasing the contributions to the store of mathematical knowledge made by the members of the vibrant and self-sustaining national community