This article examines the relationship between power fluctuations in the el
ite power system and the frequency of war. A theory is developed and tested
using a new dataset of elite powers and elite power wars. The theory posit
s that fluctuations in the elite power system are related to war among elit
e powers due to an increase in uncertainty that accompanies such fluctuatio
ns. The theory is logically extended to contend that as elite power systems
age (move temporally away from the point of fluctuation) the frequency of
war will decrease, due to the decline of uncertainty. The theory is support
ed by analysis employing an existing dataset collected by Jack Levy, as wel
l as a new elite war dataset. Additionally, in terms of the type of fluctua
tion and war, the study finds that as the system becomes more complex the i
ncidence of war also increases.