The article uses the second-order perspective developed by Niklas Luhmann to re-examine the relation between globalization and sovereign states. From a second-order perspective, globalization is redefined as a self-description of society supported by the practice of comparing sovereign states with other sovereign states for the purpose of determining what is global at the present moment in time. The article develops a genealogy in order to account for this particular practice of comparing states with each other in historical terms. The genealogy proceeds by treating the states as spatial units within spatial divisions, while four distinct types of spatial division are discussed and aligned in one sequence: stratified, heterogeneous, homogeneous and meta-division. In some cases, not all spatial units are states. Accordingly, states are not always or not only compared with other states. In this way, the genealogy shows that the practice of comparing states in action behind globalization as a self-description of society is linked with the last two forms of spatial division specifically.