King Bagrat III expelled the Turks from the Eastern provinces, threw off his allegience to Constantinople and established his rule over the Abkhazis, Kartvelians, Ranians, Kakhetians and the Armenians, unifying all Georgia. Giorgi III, Bagrati's grandson, was the first to assume the title of Shahanshah (King of Kings) and Master of all the East and West. His reign, and that of his successor, his daughter Thamar the Great, are seen as the 'golden age' of Georgian history, the era of empire, diplomatic success, heroic triumphs at arms against the infidel, great learning, cultural, spiritual, and artistic flowering. However, within two reigns the irrepresible westward advance of Mongol power proved too great.

The Great Khan took advantage of a missunderstanding amongst the Georgian nobles to split the power of the dynasty by appointing two rival Kings. Davit VII Ulu Giorgishvili, of the male but illegitimate line, being established as senior ruler in Mtzkheta, in Kartli. Davit VI Narin, representing the legitimate but female line, fleeing to the west to establish his kingdom in Imereti. Almost simultaneously the Mongols encouraged the great magnates and provincial grandees to establish rival centres of power or direct allegience to themselves. Thereafter, the history of Georgia became a continuous and unequal, though often heroic struggle against the forces of Islam, the Persians in the southeast and the Turks in the southwest.

Dissentions and dissagreements within the Royal family had reduced the once powerful kingdom into three, Kartli, Imereti and Kakheti. Although the three kingdoms formally accepted the separation in the 1490s, competition to reunify the kingdom continued between them for another two hundred and fifty years. The eastern kingdoms of Kartli and Kahkheti fell under Persian dominion, while Imereti in the west, succumbed to the Turks. The Persian rulers insisting on appointing the Bagratide kings as their governors or viceroys provided they converted to Islam. The Turks preferred to leave the Kings of Imereti with their religion, but to govern with a heavy hand. These long years of subjugation saw the country devastated and plundered of its wealth and treasures, its churches and monuments raised to the ground, its population removed to far off lands, and its women sold as prized slaves throughout the Muslim world.

Muslim converts amongst the Bagratides and the Georgian nobility, came to play important roles in Persian affairs. Several princesses and noblewomen married into the ruling families of Persia, while their fathers and brothers gained important posts. Georgian men-at-arms and military officers were amongst the most respected in the Persian service, becoming kingmakers, more than once. The weakening of the Safawis and the subsequent contests for power in Persia saw some resurgence of autonomy under King Vakhtang VI of Kartli. He reformed the administration, reasserted central authority, revised the legal code, and erected irrigation works and converted wastelands to cultivation. An enlightened ruler, he introduced humane laws and methods of administration, great scholar, poet, critic, translator and leader of intellectual life during the first quarter of the eighteenth century. However, war with Turkey and the subsequent agreement to divide Georgia between Turkey and Persia forced Vakhtang to flee to Russia in 1724. Given no help but allowed to settle there, he died in the city of Astrakan in 1737. His family and descendants were absorbed into the Russian nobility.

The rise to power of Nadir Shah Afshar in Perisa saw another change in Georgia's fortunes. Nadir Shah desperately wanted allies in his deadly struggles against the Zands. He needed Georgian arms in his wars in Afghanistan and invasions of India. And he needed a bulwark against the growing power of Russia in the north. Consequently, the Georgian King was allowed to reassert his authority, resume open practice of his religion and left pretty much to himself, provided he contributed revenues and provided soldiers. Kartli and Kakheti were reunited and Taimuraz II crowned at Mtzkheta, the first king to undergo the full Christian ceremonial of ancient Georgia for over a century. He reunified the country, reduced the power of the magnates and grandees, restored cathedrals and churches, but remained at constant war with the fierce Muslim tribes, the Lazgis and Daghistanis. He pleaded for help from Empress Elizabeth of Russia, to no avail.

Irakli II, son and successor of King Taimurazi, had been made King of Kakheti under his father in 1744. On his succession, he retained full control over both kingdoms, ruling them with a strong hand. He served under Nadir in Afghanistan and India, and is considered to be a gifted military strategist, who fought forty battles being victorious in most. Taking advantage of continuing dissention in Persia he succeeded in his appeal for Russian aid, negotiating the Treaty of Giorgievsk in 1783. This made Kartli and Khakheti a unitary Russian protectorate, in exchange for Russian military aid against the Turks and Persians. A promise tested but not fulfilled when Aga Muhammad Qajar fell on Tiflis with an army of 35,000. King Irakli and his grandson, King Solomoni II of Imereti were left to defend Georgia alone with forces numbering no more than 3,000. They repulsed the Persians three times, before being reduced to 150 diehards who fled into the mountains with their aged King who refused to negotiate.

King Irakli bided his time in the hills until the Russians eventually relented and sent a large army to drive the Persians out. They again withdrew, leaving the Georgians defenceless against an Aga Muhammed bent on revenge. They were only saved by his assassination at Shusha in 1797. Irakli II died six months later, leaving his throne to his weak, fat, lazy though devout son Giorgi XII. King Irakli, under the influence of his third wife, Queen Darejan, had altered the line of succession in favour of his younger sons. One of Giorgi's first acts on becoming ruler was to secure the Russian Master's agreement to recognise his eldest son as Heir Apparent and successor. This left him facing insurrections led by his half-brothers. Prince Farnavazi allied himself to the fearsome Lazgis and devastated parts of the kingdom. His other brothers, ensconced on the large domains assigned to them by their late father, ignored his authority and fermented rebellion. Devoid of stomach for any contest, the dying ruler was persuaded to resign his kingdom to the Russian Master. This he did in return for the recognition of himself and his own heirs as titular Kings of Georgia. However, while his envoys were in Russia still negotiating the terms of the new treaty, Emperor Paul decided to annex the kingdom outright. He issued a manifesto unilaterally annexing the realm to the Russian crown on 18th January 1801 o.s. The annexation was confirmed by Emperor Alexander I on 12th September 1801 o.s., shortly after Paul's death.

The Russian military detachment sent to put the annexation into effect did not arrive in Tiflis until April 1802. At first the Russians faced considerable opposition, Giorgi's widow, Queen Miriami, arranging for the assassination of the Russian Governor General Lazarev. Soon afterwards, Prince Davit, King Giorgi's Heir Apparent, and several members of the Royal Family were deported to Russia. Prince Aleksandri, meanwhile, threw in his lot with the Persians and joined the colours of Crown Prince Abbas Mirza, harrasing the Russians from across the border for several years thereafter. In 1812 rebels proclaimed as King, Prince Grigori, a son of Prince Ioane, King Giorgi XII's second but favourite son. He was swiftly captured and deported to Russia. Unpurturbed, Prince Aleksandri, raised several further rebellions in the years that followed. The most serious of these being in 1821-1822, when the Osettians revolted but were brutally crushed by the Russians. Gradually, Russian control extended into the remaining Georgian territories, each being annexed one after the other over a period of sixty-five years.

Solomon II, King of Imereti was persuaded to accept a Russian protectorate in 1804, but fled into Turkish territory when he recived prior warning of a Russian plot to kidnap and deport him to Russia in 1810. Although he crossed the broder several times and fermented several insurrections, he died a broken man, at Trebizond in 1815. Without legitimate issue, he had appointed his cousin, Prince Konstantini, as his Heir Apparent and designated successor. The only son of King Davit II, Konstantini was taken to Russia and commissioned into the Russian army. His descendants and relatives were received into the ranks of the princely houses of the Russian Empire.

Abkhazia was made into a protectorate in 1810, after the Christian son of a previous ruler was persuaded to rebel against his Muslim uncle. The principality was occupied by Russian troops but they tired of their unruly vassal and his unruly subjects, annexing the principality outright in 1864. The Guria accepted Russian protection in 1811. The province enjoyed an autonomous existence under the rule of its own Gureli princes. However, the principality was annexed outright in 1830, after the Regent Princess Sopio allied herself with the Turks in the war of 1828-1829. Svania faired little better than her neighbours and was annexed in 1858, after their quarrelsome Prince, Konstantini, was deposed and executed for opposing Russian encroachment.