Agha Mohammad Khan demanded that Heraclius II renounce the Treaty of Georgievsk, which had been signed several years earlier, denouncing dependence on Persia and agreeing to Russian protection and assistance in its affairs. He demanded that Heraclius II again accept Persian suzerainty in return for peace and security. The Ottomans, Iran's neighbouring rival, recognized Iranian rights to Kartli and Kakheti for the first time in four centuries. Heraclius appealed to Empress Catherine II of Russia for at least 3,000 Russian troops; although he received no response (leaving Georgia to fend off Persia alone), he rejected Agha Mohammad Khan's ultimatum. Agha Mohammad Khan invaded the Caucasus, crossing the Aras and recapturing Shirvan, the Erivan, Nakhchivan, Derbent, Talysh, Shaki and Karabakh Khanates, and Igdir. The Battle of Krtsanisi resulted in the sack of Tiflis and the reintegration of Georgia into Iran. When he returned with 15,000 to 20,000 Georgian captives, Agha Mohammad was crowned shah in 1796 on the Mughan plain, as Nader Shah had been sixty years earlier.