Yes / This study explores the underdog brand biography dimensions that emerging-country consumers identify with (Study 1) and attempts to uncover the effects of these dimensions on brand affinity and purchase intention moderated by self-identity and brand trust (Study 2). Study 1, using data from 359 young Indians, reveals three underlying dimensions integral to underdog brand biography in emerging markets. Study 2 employs an experimental setup with a single-factorial design among 332 young Mexican consumers to investigate the direct effects of three identified underdog brand biography dimensions on purchase intention, mediated by brand affinity and moderated by consumer self-identity and brand trust. Study 1 reveals three dimensions underlying underdog brand biographies: unfavorable circumstances, striving in adversities and passion, and persistent will to succeed. Study 2 reveals that consumers with higher self-identity demonstrate greater purchase intentions for an underdog brand than a top dog one. This study delineates the link between different dimensions of underdog brand biographies with brand affinity and purchase intention in emerging countries and builds on the understanding of the moderating role played by self-identity and brand trust. The results indicate that marketers can successfully use underdog narratives to influence consumer decision-making, thereby increasing brand affinity and purchase intention.