Understanding how physical forces shape the coupled processes of cortical folding and neural connectivity is essential for explaining both normal brain development and the origins of neurodevelopmental disorders. Although prior theories have emphasized genetic and biochemical drivers of gyrification, the mechanical regulation of axon pathfinding within a folding cortex remains incompletely understood. We present a multiscale mechanical framework that links differential tangential growth of the cortical plate with stress dependent axon growth and reorientation within the subplate. Building on the differential tangential growth hypothesis, growing axon bundles are embedded within a finite element model of cortical folding. Each fiber evolves through baseline stochastic extension, tensile stress induced elongation, and active alignment toward the direction of maximum principal tensile stress. Our simulations show that regions forming gyri experience predominantly radial tensile stress, which accelerates axonal growth and promotes radial alignment, consistent with experimentally observed higher axon density in gyri compared with sulci. Variations in fiber stiffness, growth rate, and the stiffness ratio between cortex and subplate significantly influence both fold morphology and connectivity patterns, indicating that mechanical heterogeneity modulates surface geometry and local circuit organization. Timing also plays a critical role: fibers initiating growth after folding begins are more strongly reoriented by stress and tend to form U shaped short association fibers, whereas early fibers form more direct projection like tracts. Model predictions agree with in vivo diffusion tensor imaging, including preferential streamline clustering in gyri and characteristic orientation patterns near gyral crowns and sulcal fundi. By integrating cortical mechanics with axon level guidance, this framework offers a mechanobiological explanation for the organization of short range association fibers and long range tracts, and provides a foundation for studying how altered mechanical environments in conditions such as lissencephaly, polymicrogyria, or preterm birth may disrupt connectivity and brain development.