This paper integrates the studies of various countries' behaviors, e.g., waging wars and entering into military alliances, into a general framework of \emph{countries' relation formation}, which consists of two components, i.e., a static game and a dynamical system. Aside from being a stand-alone framework itself, this paper can also be seen as a necessary extension of a recently developed \emph{countries' power allocation game} in \cite{allocation}. We establish certain theoretical results, such as pure strategy Nash equilibrium existence in the static game, and propose several applications of interest made possible by combining both frameworks of countries' power allocation and relation formation.