A comprehensive study of the mortality of Norse gods, with close readings of the Prose Edda, Poetic Edda and Saxo Grammaticus' Gesta Danorum. Divinity usually implies immortality. The very phrase "gods and mortals" highlights an ontological gap between two distinct categories of existence: immortal deities and transient humans. This divide, however, does not hold true in the Scandinavian mythological tradition, where the gods themselves are mortal. This mortality is central to myths such as those of Baldr and of Ragnarøk, and affords the Norse gods narrative potential, that is unparalleled in other traditions, such as those inherited from antiquity. The first half of this study explores some salient consequences of this attribute, highlighting the striking anthropomorphism of the gods. The second half takes a more diachronic approach, examining the prehistory of the group of gods who became known as the Æsir and arguing that they developed from non-anthropomorphic divine forces shaped by and mobilized in ideologies of leadership and warfare in pre-Christian Northern Europe. By examining how divine mortality not only drives Norse mythic narratives but also reflects wider patterns of thought and belief, including early medieval theories of rulership and the sacralization of human excellence, this book reconsiders the boundaries between godhood and humanity in pre-Christian Scandinavia and, in doing so, questions what it means to be a god.