This study investigates the relationship between self-reported personality traits and zodiac sign descriptions, exploring the mediating roles of the Barnum Effect (acceptance of vague, universal personality descriptions) and cultural belief in astrology. Using a mixed-methods design, 1,200 participants from India (high astrology-belief culture) and Sweden (low astrology-belief culture) completed the Big Five Inventory (BFI), rated their zodiac sign’s accuracy, and evaluated fake "personalized" Barnum-type descriptions. Quantitative analysis revealed no significant correlation between zodiac signs and actual personality traits (BFI). However, participants who strongly believed in astrology overestimated alignment (p<.001), with Indian participants showing stronger Barnum-driven acceptance than Swedes (η² = .12). Qualitative interviews highlighted astrology’s role in identity construction and coping. Results suggest zodiac-based personality alignment is culturally mediated and driven by cognitive biases, not astrological validity.