In 2004-2005, American Jewry will celebrate the three-hundred-fiftieth anniversary of its founding. Attention will focus in multiple directions: the majority American ambiance and its stances toward Jewish immigrants; the diverse ways in which Jews have adapted to America; the creative directions Jewish life has taken in America; and the problematics of Jewish existence in an open society. The issue that I would like to focus upon briefly takes us back to the Old World and involves the willingness, indeed the desire, of Jews to relocate in the New World in 1654, the ongoing migration of Jews to America thereafter, and the incessant Jewish movement within America as new frontiers have recurrently opened. The early and continuing migration of Jews westward should hardly be taken for granted. To be sure, a Jewish propensity for migration has regularly been assumed, out of a sense that Jews have been forever a wandering group, a people whose history comprises a seemingly endless series of displacements. Such a sense of the Jewish past, however, is largely rooted in theology. A close look at the realities of Jewish migration suggests that, for long periods of time, Jewish population patterns were in fact quite stable. Indeed, we can identify a critical turning point at which Jews broke out of the prior limits of their settlement, began moving to new areas, and rooted themselves in large numbers in western Christendom. This turning point and its implications should be properly acknowledged as critical to the subsequent movement of Jews westward into the exciting and challenging New World.