The X-Men #14

Published in November 1965, The X-Men #14 serves as a pivotal entry in the early Marvel era, marking the first appearance of the Sentinels. Created by writer Stan Lee and artist Jack Kirby, the issue reflects the era's growing cultural anxiety regarding rapid technological advancement and nuclear proliferation. The narrative introduces Bolivar Trask, an anthropologist who constructs the giant robots to protect humanity from the perceived threat of mutants, establishing the Sentinels as enduring metaphors for prejudice and systemic persecution within the franchise.

The visual design of the Sentinels is a quintessential example of Kirby's kinetic, blocky aesthetic, characterized by a sense of imposing scale and mechanical menace that stood in stark contrast to the more human-sized threats of the preceding issues. While early X-Men stories often struggled to find a consistent footing in the crowded Silver Age landscape, this issue is widely cited by historians as the moment the series defined its core thematic conflict—humanity's fear of the 'other'—which would remain the central pillar of X-Men lore for decades to come.