While there are many religious theocracies and secular democracies around the world, very few countries have found a way to bridge the gap between religion and politics. But in Lebanon, not only does there exist a democracy within a larger religious structure, there are actually 18 official religions built into the country's parliamentary system. So let's take a look at how and why a dozen and a half different sects are able to rule over one country.
Lebanon's multi-religion government actually stems from its invading predecessor: the Ottoman Empire. From about 1516 to 1918, Lebanon was under the jurisdiction of this Empire, and around the 1830s, a system of reorganization by the Ottomans called "Tanzimat," declared that all citizens were equal under the law, regardless of their religious affiliation. For Lebanon, this was a problem, as the country's many different religions, spanning Islam, Christianity, and Judaism, had each established their own legal rules, which were implicitly unequal.
Before Tanzimat, the Ottoman Empire stressed religious pluralism, with each religion considered it's own nation-like entity, called a "millet." Together these millets comprised the Empire, and had individual legal protections. Today, Lebanon operates under a similar system of religious pluralism called "confessionalism."
Aljazeera: Lebanon's election system
NY Times: U.S.-Backed Alliance Wins in Lebanon
BBC: Lebanon: Michel Aoun elected president, ending two-year stalemate