In the 1220s and 1230s, the Mongol Horde appeared in the Near East. Having conquered the northeastern part of China (1211-1215), the Mongol leader Genghis Khan marched out against Central Asia, launching an offensive against the Kindom of Khwarizm (1200-1220). A detachment of the Mongol army, fresh from victory against Khwarizm, attacked Georgia several times in the early 1220s. By 1240 the entire country was under the Mongol yoke. The Mongols put King Demetre II to death, leading to his canonization as Demetre the Self-Sacrificer. In the first half of the 14th century Giorgi V the Brilliant (1314-1346) pursued a wise, flexible policy aimed at overthrowing the Mongol yoke and restoring Georgia's sovereignty and unity. In 1329, Giorgi V incorporated Western Georgia and in 1334 the principality of Samtskhe. Gradually, Georgia had managed to free herself from Mongol rule.
Having been liberated from the Mongol oppression, the country began to revive, but this period was destined to be short-lived. It wasn’t long before the cruelest conqueror to have ever invaded Georgia, Tamerlane, began attacking Georgia. A military genius, Tamerlane had conquered India in a brief 14 months, but Georgian resistance and terrain proved to be a challenge for the brilliant strategician. Tamerlane spent more than 15 years trying to subdue Georgia! From 1386-1403, he attacked Georgia 8 times and left terrible devastation behind, destroying cities and slaughtering the Christian population (though it should be noted he rarely discriminated—Baghdad suffered greatly after being put to the sword and its Muslim occupants were murdered).
During the first decade of the 15th century, the Ottoman Turks began to make similarly destructive inroads into Georgia. In 1453 the Ottomans finally captured Constantinople, destroying the Byzantine Empire. In 1461, the Empire of Trebizond fell to the Turks and in 1475 the Ottoman Sultan established his authority over the Khanate of Crimea, along the northern coast of the Black Sea. Georgia was now practically cut off from international trade routes and deprived of the chance to establish direct contact with other European countries. This worsened the economic and cultural decline of the country; commerce and handicrafts fell into decay and some cities ceased to function due to the disruption of the never-ending wave of invasions. The royal power weakened and the isolationist tendencies of individual feudal lords became readily apparent.
The process of the decline and disintegration of the unified Kingdom of Georgia that had begun in the 13th-14th deepened in the 15th century. At the turn of the 15th and 16th centuries, Georgia broke up into separate political units. Out of the ruins of the Georgian state rose the Kingdoms of Kartli, Kakheti and Imereti, and the principalities of Samtskhe, Odishi, Svaneti, Guria, and Abkhazia. Divided into this myriad of administrative units, Georgia was wracked by feuds.
In the 16th century, Persia and Turkey contended for supremacy in the Near East. Georgia turned once again turned into a stomping ground for major regional powers to fight for supremacy. In 1513, King David V of Kartli (1505-1525) incorporated the Kingdom of Kakheti but failed to preserve this unity. In 1522, Shah Ismail I of Persia attacked Kartli. Taking and sacking Tbilisi, he stationed his garrison in its citadel. Then he took Samtskhe-Saatabago, returning to Persia loaded with captives and plunder. In 1524, the Georgians liberated Tbilisi.
At the same time, Western Georgia became a target of Turkish aggression. According to the Treaty of Amasya between Persia and Turkey, Western Georgia fell under Turkish influence, while Eastern Georgia and the eastern part of Samtskhe-Saatabago would be subject to Persian rule. After the conclusion of this treaty, the Georgians' struggle to preserve and regain their independence continued under much more difficult conditions than before. Kartli never surrendered, and King Simon I even managed to rout the Persian Army in 1556. Conversely, by submitting to the Shah of Persia, Kakheti succeeded in preserving peace but at the cost of its independence.
At the beginning of the 17th century Shah Abbas I of Persia drove the Turks out of Armenia, Kartli and Kakheti. The Turkish oppression was merely replaced by Persian authority. In response, the Ottomans and their Crimean Tatar allies invaded Kartli in 1609. In 1614, Shah Abbas I attacked Kakheti. Then, invading Kartli, he occupied all the fortresses with his own soldiers. In 1615, Kakheti rose against the Persians, forcing them out of the castles and redoubts of the region. This insubordination brought swift retribution and in 1616, Abbas I again invaded Kakheti and Kartli, razing many fortresses, churches, monasteries, and palaces. Orchards and vineyards were cut down and countless civilians were killed. One hundred thousand Georgians were taken prisoner; to this day their descendants live in the province of Fereidan in Iran.
Finding herself encircled by aggressive, Muslim states and with a view to preserving her statehood, Georgia appealed to Russia for help. The largest nearby Christian power was experience a resurgence and revival of its own under Tsar Peter the Great. With the Tsar’s help, King Vakhtang VI (1703-1724) hoped to throw off Persian domination once and for all. In 1720 Peter the Great had swung his gaze southward and began engaging in diplomatic negotiations with the states of Transcaucasia. The Tsar urged the King of Kartli to join Russia, promising to rid Georgia of the oppression of the "infidels." The intersection of their respective national interests led to a natural military and political relationship between Kartli and Russia. In June 1722, Peter I issued a manifesto calling for a military campaign against Persia. The Georgian and Armenian armies met at Ganja (in modern day Azerbaijan) but the Russian army failed to arrive as scheduled. Due to numerous political difficulties, both domestic and international, Russia had been forced to call off their war on Persia. In retaliation against the Georgians and Armenians, the Shah dethroned Vakhtang Vl and gave Kartli to Constantine, the ruler of Kakheti. Constantine laid siege to Tbilisi with an army of Daghestani mercenaries in 1723, capturing and sacking the capital. Vakhtang VI was forced to retreat to Shida Kartli while Kakhetian forces occupied Tbilisi. Later that same year, in an event showcasing the chaos and peril of those times, Tbilisi was seized by a Turkish army.In the 1724 Treaty of Contstantinople, the Russian and Ottoman Empires formally divided Persian and South Caucasian territories into their own spheres of influence. The Ottomans recognized the western and southern coasts of the Caspian Sea as the eminent domain of Russia while the Russians, in turn, granted eastern Georgia, Armenia, Azerbaijan, and much of northern Persia to the Turks. For the time being the plan for liberating Georgia had failed. With Peter the Great’s blessing and consent, the deposed and disgraced Vakhtang VI left for Russia with his family, his closest compatriots, and a large retinue on June 15, 1724.