Catholic Patriarch of Constantinople

The Latin Patriarch of Constantinople was an office established as a result of Crusader activity in the Near East. The title should not be confused with that of the Eastern Orthodox Patriarchate of Constantinople, an office which existed before and after.

Before the East–West Schism in 1054, the Christian Church within the borders of the ancient Roman Empire was effectively ruled by five patriarchs (the "Pentarchy"): the Bishop of Rome (who rarely used the title "Patriarch") and those of Constantinople, Jerusalem, Alexandria, and Antioch.

In the West the Bishop of Rome was recognized as having superiority over the other Patriarchs, while in the East, the Patriarch of Constantinople gradually came to occupy a leading position. In the East the Pope was generally considered first among equals, but not a direct superior.. The sees of Rome and Constantinople were often at odds with one another, just as the Greek and Latin Churches as a whole were often at odds both politically and in things ecclesiastical. There were complex cultural currents underlying these difficulties, including the fact that in the West feudal models began to influence the way of viewing relations within the Church. The tensions led in 1054 to a serious rupture between the Greek East and Latin West called the East–West Schism, which while not in many places absolute, still dominates the ecclesiastical landscape.

In 1204, the Fourth Crusade invaded, seized and sacked Constantinople, and established the Latin Empire. This was not the doing of the Bishop of Rome, the Pope. Initially he spoke out against the fourth crusade. In writing to his legate the pope said, in part "How, indeed, is the Greek church to be brought back into ecclesiastical union and to a devotion for the Apostolic See when she has been beset with so many afflictions and persecutions that she sees in the Latins only an example of perdition and the works of darkness, so that she now, and with reason, detests the Latins more than dogs?"

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