Evidence of settlement in the area stretches back more than 6000 years, but Georgians like the legend that King Vakhtang Gorgasali of Kartli founded Tbilisi in the 5th century AD. The story runs that when the king was hunting, a wounded deer fell into a hot sulphur spring here and was miraculously healed. In fact, Gorgasali won the already-existing town back from the Persians, and moved his capital here from Mtskheta. But there’s no doubt that it was Tbilisi’s magnificent hot springs that gave it its name (Georgian tbili means warm).
The city's location, commanding a crossing of the Mtkvari River on age-old trade routes between Asia and Europe, has always been prized. In 645 Arabs captured Tbilisi and kept it as an emirate for four centuries, but in 1122 King David the Builder (Davit Aghmashenebeli) made it capital of his united Georgia, building a palace near the Metekhi Church. David invited Armenian artisans and traders to settle here, and Armenians remained highly influential in Tbilisi until the 20th century. Under David and his great-granddaughter Queen Tamar, Tbilisi grew into a multi-ethnic city of 80,000 people, known for its production of weapons, jewellery, leather and silk clothing. The golden age was ended with a vengeance by the Mongols in 1235, who were followed by the Black Death, and then conqueror Timur (Tamerlane), who destroyed the city in 1386.
Tbilisi recovered somewhat under Persian rule during the 17th and 18th centuries, and in 1762 it became capital of a semi-independent eastern Georgia under King Erekle II. Erekle’s protector Russia, however, withdrew its troops to fight the Turks, allowing Agha Mohamed Khan to inflict Persia’s most devastating assault in 1795. His army killed tens of thousands and burnt Tbilisi to the ground. Russia annexed Georgia in 1800 and recreated Tbilisi in the imperial mould, laying out wide streets and squares. By 1899 it had 172,000 people, one-third of them Armenian and a quarter each Georgian and Russian. Swabian Germans escaping religious persecution at home also moved to Tbilisi in large numbers during the early 19th century, creating a settlement known as Neu-Tiflis (New Tbilisi) around what is now Marjinashvili metro station, and contributing much to Tbilisi's cosmopolitan makeup. Neu-Tiflis was incorporated into the city proper in 1862, but Germans remained influential in Tbilisi until the Soviet annexation in 1921.
The Soviet era saw huge growth for Tbilisi as Georgians flooded in from the countryside as the city industrialised and massive housing projects were built. The city was also a centre of opposition to the late Soviet regime, producing a number of significant dissidents and artists that challenged the status quo in the 1970s and 1980s. After Georgian independence in 1991, Tbilisi became a battleground in the civil war that erupted. The 1990s were dark years – literally, with frequent electricity blackouts – as living standards sank and corruption and crime became rife. But since the Rose Revolution of 2003, crime has almost disappeared and Tbilisi has enjoyed a flood of investment and refurbishment.