FOUNDED: 325 C.E.
RELIGION AS A PERCENTAGE OF WORLD POPULATION: 3.5 percent

Overview

Along with Roman Catholicism and Protestantism, Eastern Orthodoxy is one of the three major branches of Christianity. It exists as a fellowship of 18 independent or semi-independent church bodies, each headed by a bishop (sometimes called a patriarch). The largest are the Russian Orthodox Church and the Romanian Orthodox Church. The honorary head of Eastern Orthodoxy is the patriarch of Constantinople (Istanbul, Turkey), who holds no jurisdiction over the church as a whole. Today most Eastern Orthodox Christians live in Russia, the Balkans, and the Middle East.

In Greek the word "orthodoxy" (orth and doxa) means "correct praise" or "correct teaching." The first use of the word "orthodox" by Greek theologians occurred in the fourth century C.E., when what came to be known as "Orthodox Catholic" Christianity confronted "erroneous" teaching. The essential tenets of...