1. An object management system, comprising: a virtual space divided into an ordered plurality of partial spaces; at least one object management device comprising an object management unit for managing at least one object allocated in a target region formed of a sequential order of partial spaces in the virtual space; at least one client device specifying a partial space including a position where the object is to be allocated, and instructing the at least one object management device to allocate the object in the specified partial space of the virtual space, wherein the at least one object management device, in response to the allocation instruction, determines whether or not the specified partial space is included in the target region based on the ordering relation of partial spaces, and the at least one object management device allocates the object in the specified position of the partial space when the partial space is determined to be included in the target region.