A cellular automaton for simulating territories is presented. In it, cells have a certain amount of markings of two different groups. The amount of markings for each group gets higher based on the amounts of that group in neighboring cells and the amount of markings of the opposite group in the current cell to simulate an avoidance tendency. The markings also decay at a certain rate. Depending on the parameters, the simulation can end up in a mixed state, where there are no clear territories, or a segregated state, where both groups have a large amount of connected cells where they are dominant. Small changes in these parameters can change the outcome significantly. Unless an unconsidered combination of parameters changes it, this model is not the most realistic. It could however have uses in more influence-based processes, such as the spread and boundaries of languages or religion.