IN June 1772, Russian forces bombarded, stormed and captured Beirut, a fortress on the coast of Ottoman Syria. The Russians were backing their ally, a ruthless Arab despot. When they returned the next year, they occupied Beirut for almost six months. Then as now, they found Syrian politics a boiling cauldron of factional-ethnic strife, which they tried to simplify with cannonades and gunpowder.

Today, President Vladimir V. Putin has many motives in Syria, but we should keep in mind Russia’s vision of its traditional mission in the Middle East, and how it informs the Kremlin’s thinking. And not just the Kremlin: Russia’s Orthodox Church spokesman said that Mr. Putin’s intervention was part of “the special role our country has always played in the Middle East.”

Russia’s ties to the region are rooted in its self-assigned role as the defender of Orthodox Christianity, which it claimed to inherit from the Byzantine Caesars after the fall of Constantinople in 1453 — hence “czars.” The czars presented Moscow not just as a Third Rome, but also as a New Jerusalem, and protector of Christians in the Balkans and the Arab world, which, including the Holy Places of Jerusalem, were ruled by the Ottomans after 1517.

Devout peasants believed before they died that they should make the pilgrimage to Jerusalem and dip their shrouds in the Jordan. Until 1917, the czars blessed the waters of “the Jordan” every Jan. 6, in the Moscow, or later the Neva, River.

Russia’s first major intervention began in 1768, when Catherine the Great went to war with the Ottomans, and Count Alexei Orlov, the brother of her lover Grigory, sailed the Baltic fleet through the Strait of Gibraltar to rally rebellions in the Mediterranean. Recruiting Scottish admirals, Orlov annihilated the Ottoman fleet at Chesme, after which Russians temporarily dominated the eastern Mediterranean. ...