The Holy Roman Empire was a multi-ethnic union of nations and territories in central Europe that developed during the Middle Ages, and gradually decreased in power over centuries. The Empire was never as centralized and politically united as that of nations like France, and instead evolved into a decentralized, limited elective monarchy made up of hundreds of principalities, duchies, territories, counties, Free Imperial Cities, ecclesiastical states, and other domains.
The leader of the Empire, the Holy Roman Emperor, was elected. The power of the Emperor was limited, and while the various princes, lords, and kings of the Empire were considered vassals and subjects to the Emperor, they also possessed certain privileges that gave them a sense of sovereignty within their territories.
With the Seventy Years' War devastating much of Europe, the Empire became further disunited in terms of politics and identity, and many states within the Empire were expanding their power rapidly. Eventually, minor conflicts and nationalism led to the demise of the Empire, however intergovernmental organizations were later established in place of the Empire for economic trade and security.