A buffer state is a country geographically lying between two rival or potentially hostile great powers. Its existence can sometimes be thought to prevent conflict between them. A buffer state is sometimes a mutually agreed upon area lying between two greater powers, which is demilitarized in the sense of not hosting the military of either power (though it will usually have its own military forces). The invasion of a buffer state by one of the powers surrounding it will often result in war between the powers. Research shows that buffer states are significantly more likely to be conquered and occupied than are nonbuffer states. This is because "states that great powers have an interest in preserving—buffer states—are in fact in a high-risk group for death. Regional or great powers surrounding buffer states face a strategic imperative to take over buffer states: if these powers fail to act against the buffer, they fear that their opponent will take it over instead. By contrast, these concerns do not apply to nonbuffer states, where powers face no competition for influence or control." Buffer states, when authentically independent, typically pursue a neutralist foreign policy, which distinguishes them from satellite states. The concept of buffer states is part of a theory of the balance of power that entered European strategic and diplomatic thinking in the 18th century. Examples Americas Bolivia, created by Gran Colombia as a buffer between Peru and Argentina during the Upper Peru question. Uruguay, served as a demilitarized buffer between Argentina and the Empire of Brazil during the early independence period in South America. Paraguay, maintained after the end of the Paraguayan War in 1870, as a buffer separating Argentina and Brazil. Georgia, a colony established by Great Britain in 1732 as a buffer between its other colonies along the Atlantic coast of North America and Spanish Florida. Ecuador, served as a "cushion state" between Colombia and Peru, which had a bigger extension and military force and fought a war in the 1820s in what is now Ecuador. Asia Multiple buffer states played major roles during the Roman–Persian Wars (66 BC – 628 AD). Armenia was a frequently contested buffer between the Roman Empire (as well as the later Byzantine Empire) and the various Persian and Muslim states. North Korea, during and after the Cold War, has been seen by some analysts as a buffer state between the military forces of China,