The exploration of one‐dimensional (1D) magnetism, frequently portrayed as spin chains, constitutes an actively pursued research field that illuminates fundamental principles in many‐body problems and applications in magnonics and spintronics. The inherent reduction in dimensionality often leads to robust spin fluctuations, impacting magnetic ordering and resulting in novel magnetic phenomena. Here, we explore structural, magnetic, and optical properties of highly anisotropic two‐dimensional (2D) van der Waals antiferromagnets that uniquely host spin chains. First‐principles calculations reveal that the weakest interaction is interchain, essentially leading to 1D magnetic behavior in each layer. With the additional degree of freedom arising from its anisotropic structure, we engineer the structure by alloying, varying the 1D spin chain length using electron beam irradiation, or twisting for localized patterning, and calculate spin textures, predicting robust stability of the antiferromagnetic ordering. Comparing with other spin chain magnets, we anticipate these materials to bring fresh perspectives on harvesting low‐dimensional magnetism.This article is protected by copyright. All rights reserved