After Heraclius II refused to denounce the treaty with Russia and to voluntarily reaccept Iran's suzerainty in return for peace and prosperity for his kingdom, Agha Mohammad Khan invaded Kartli-Kakheti, captured and sacked Tbilisi, effectively bringing it back under Iranian control.

The following years, which were spent in confusion, culminated in 1801 with the official annexation of the kingdom by Paul I within the Russian Empire during the nominal ascension of Heraclius's son George XII to the Kartli-Kakhetian throne.

Following the Russo-Persian War of 1804–1813, Iran officially ceded the kingdom to Russia, marking the start of a Russian-centred chapter in Georgian history.

In the ensuing period Heraclius II made alliances with the khans of the area, established a leading position in the southern Caucasus, and requested Russian aid.

Shortly after, in 1762–1763, during Karim Khan's campaigns in Azerbaijan, Heraclius II tendered his de jure submission to him and received his investiture as vali ("governor", "viceroy") of Gorjestan (Georgia), the traditional Safavid office, which by this time however had become an "empty honorific".

[6] In the same decades, the copper coins struck at Tbilisi bore three types of iconography; Christian, Georgian, "and even" Imperial Russian (such as the double-headed eagle).

[6] While Heraclius II's court maintained a certain Persian-type pomp, and he himself dressed in the Persian style as well, he launched an ambitious program of "Europeanization" which was supported by the Georgian intellectual élites; it was not overwhelmingly successful however, because Georgia remained physically isolated from Europe and had to expend all available resources on defending its precarious independence.

[3] He strove to enlist the support of European powers, and to attract Western scientists and technicians to give his country the benefit of the latest military and industrial techniques.

[7] A limited Russian contingent of two infantry battalions with four artillery pieces arrived in Tbilisi in 1784,[9] but was withdrawn, despite the frantic protests of the Georgians, in 1787 as a new war against Ottoman Turkey had started on a different front.

For Agha Mohammad Khan, the re-subjugation and reintegration of Georgia into the Iranian Empire was part of the same process that had brought Shiraz, Isfahan, and Tabriz under his rule.

[9] It was therefore natural for Agha Mohammad Khan to perform whatever necessary means in the Caucasus in order to subdue and reincorporate the recently lost regions following Nader Shah's death and the collapse of the Zands, including putting down what in Iranian eyes was seen as treason on the part of the vali of Georgia.

[11] Heraclius appealed then to his theoretical protector, Empress Catherine II of Russia, asking for at least 3,000 Russian troops,[11] but he was ignored, leaving Georgia to fend off the Iranian threat alone.

[11] With half the number of troops Agha Mohammad Khan had crossed the Aras river, he now marched directly upon Tbilisi, where it commenced into a huge battle between the Iranian and Georgian armies.

In the same year, following the power vacuum in Georgia that got created mainly due to Agha Mohammad Khan's death, the Russian troops entered Tbilisi.

[20] Paul tentatively accepted this offer, but before negotiations could be finalized, he changed his mind and issued a decree on December 18, 1800 annexing Kartli-Kakheti to Russia and deposing the Bagratids.

The war eventually ended with the Treaty of Gulistan, which forced Iran to officially cede eastern Georgia, Dagestan, as well as most of the modern-day Azerbaijan Republic to Russia.