We value many things for their historical significance--for instance, the Parthenon, Gettysburg, the redwood forests, and the tea ceremony. While they may also be beautiful, educational, or useful, we often value them simply in virtue of their historical properties. This mode of valuation carries with it a suite of common assumptions: what we value for its history is irreplaceable, it demands preservation, and we should value it only if we have a personal stake in its history. My dissertation interrogates these seemingly intuitive commitments, and explores the moral, evaluative, and political consequences of rethinking them. I develop an account of the norms governing our interactions with historically valuable objects and places, yielding an improved understanding of the values latent in such diverse examples as heirlooms, relationships, artworks, artifacts, and historic sites. It also, I argue, sheds light on other important sources of value, including persons and the natural environment. It is often thought that things worth valuing for their historical properties are necessarily irreplaceable, and that this fact makes a defining contribution to their distinctive value. For example, no candidate substitute can be valuable in the same way as my father's ring. Against this widespread view, I argue that a plausible understanding of historical significance entails that many things we value for their histories are not irreplaceable after all. What makes historically significant things worth valuing is not their irreplaceability, but rather the connection with the past that they afford. This raises the difficult question of how we can best realize a connection with the past. I argue that historical value, like value in general, fundamentally involves reasons to engage appropriately with valuable things: that is, to respond to them in a manner sensitive to the specific ways in which they are valuable, for instance, by viewing a painting, playing a sport, or savoring a fine meal. This contrasts with the views of many philosophers, who believe that the value of objects fundamentally involves reasons to preserve them. As I argue, reasons for preservation are subordinate to and explained by reasons for engagement--there is no reason to preserve even the Mona Lisa if no one can have the opportunity to engage with it. Recognizing the centrality of engagement in evaluative theory and practice has extensive implications, both in historical cases and beyond. Consider the distinction between personal and impersonal value. It is natural to think that some objects (such as family heirlooms) have merely personal value, whereas others (such as the pyramids or the Grand Canyon) have value for anyone. But how exactly are we to understand this distinction? Traditional accounts suggest that things are impersonally valuable if they would be valued from a suitably "detached" perspective. But I show that this criterion does not reliably identify things of impersonal value. On the alternative framework I propose, an object's value is impersonal if and only if it is appropriate (and therefore evaluatively permissible) for anyone to engage with it. Only a few people have reason to engage with a family heirloom, whereas the pyramids are candidates for universal engagement. Moreover, this account leaves open the possibility that the reasons that each individual has to value the pyramids can vary with that individual's particular history, interests, and capacities, unlike the shapeless "agent-neutral" reasons of the traditional view. Finally, I argue that the historical mode of valuation is often properly understood as a kind of aesthetic valuing. While many twentieth century philosophers have acknowledged the importance of art historical properties to aesthetic evaluation, I distinguish between art historical properties and the more general historically significant properties that are found both within and beyond the artworld. I then argue that these historical properties can be accommodated on a number of influential accounts of aesthetic value, and indeed, that they comprise an important dimension in aesthetic experience. This helps cement the extension of aesthetic inquiry beyond the artworld, and articulates a familiar yet surprising way in which we engage with the past.