The original settlement bearing the name Zagreb stretched along the left bank of the Medvescak brook. It entered the history in 1094 when the Hungarian king Ladislas established the Zagreb diocese.
A canonical settlement (Ka-nonicka Ves, Kaptol) developed soon after, north of the Cathedral. Zagreb was both the county castrum and the seat of the Viceroy. The episcopal Zagreb included Vlaska Street, and since 1247 a part of the land in Gradec, where Kaptol erected its tower (Popov Toranj).
On the neighbouring hill (today Gornji Grad), a fortified town Gradec (Grec, Grech) developed parallelly with Zagreb. In 1242 both parts of the town were devastated by the Ta-t-ars.
In the same year the Croato-Hungarian king Bela IV granted Gradec the so-called Golden Bull, a privilege exempting the inhabitants of Gradec from the county jurisdiction but imposing military duty to the king.
Shortly after the withdrawal of the Tatars the inhabitants started to fortify Gradec. Much of the fortification system was completed in 1266; the walls with towers and gates formed a triangular defence system around the town.
The suburb of Gradec developed below - German (sostarska) Ves and Nova Varoska Ves (today's Ilica Street), and Nova Ves from 1334 on the canonical estates north of Kaptol.
In the 15th century, with the Turkish invasion of the Turopolje region, King Matthias Corvinus allowed Bishop to fortify Kaptol. The rectangular system of walls and towers surrounding the town was finished already around 1478, and the walls around the Cathedral were completed by the bishop Toma Bakac from Esztergom, who administered the Zagreb diocese in the first quarter of the 16th century.
Kaptol and Gradec (with its new statute adopted in 1609), although two separate municipalities for centuries, started to be called Zagreb since the 16th century. Ever since Zagreb is considered to be the political centre and capital of Croatia and Slavonia (which was expressed explicitly by the Croatian Diet in 1557).
Croatian viceroys were not seated in Zagreb all to the beginning of the 17th century; Nikola Frankopan was the first to choose Zagreb as his headquarters in 1621.
The Jesuits came to Zagreb in 1606 on the invitation of the Croatian Diet and already in 1607 they moved their print shop from Ljubljana to their Zagreb collegium, to open in 1669 the academy with a curriculum comprising philosophy, theology and law. The activities of the Jesuit print shop were revived in 1695 by Pavao Ritter Vitezovic.
During the 17th and 18th centuries Zagreb suffered heavy damage caused by big fires (1645, 1674, 1706, 1731) and the plague (1647, 1682).
In 1776 the seat of the Croatian Royal Council (government) was relocated from Varazdin to Zagreb, and under Joseph II the town became the seat of the Varazdin and Karlovac Generalates. At the end of the century, funded by the city and Kapitol municipal administration, the construction of the big hospital (endowment) began; completed in 1804.

In the 19th century Zagreb saw a more intense economic, political and cultural development.
The long rivalry between the episcopal town and the free royal town gradually ceased, especially under the influence of the Croatian national revival.
The 19th-century cultural development of Zagreb is characterized by foundation of several important cultural and educational institutions: 1826 the Music Society (later Music Institute), 1829 the first music school, 1834 the first theatre stage, 1839 the Matica Ilirska (since 1874 Matica Hrvatska), 1845 People's Museum, 1866 the Yugoslav Academy of Arts and Sciences (now the Croatian Academy of Arts and Sciences), 1874 the University of Zagreb (initially comprising three faculties: Faculty of Philosophy, Faculty of Laws and Faculty of Theology).
The first railroad through Zagreb was put in traffic in 1862, the gasworks was put in operation the following year, the waterworks was introduced in 1878, horse tram in 1891, and electric tram in 1910 (the first electric power plant was opened in 1907). Development of industry started around the mid-19th century. Already in 1910 the town had more than one hundred industrial companies, the major ones being machine-building, textile, food processing and printing companies.
On 29th of October 1918, the Croatian Diet passed a resolution to break all public law relations between Croatia on one side and the Austria--Hungarian Empire on the other and join the common state of Slovenians, Croats and Serbs. Between the two World Wars Zagreb was a po-werful industrial centre. The first radio station started to broadcast in Zagreb in 1926.

With the establishment of Civil Croatia (Bano-vina Hrvatska) in 1939, Zagreb became its centre, then the capital of the Independent State of Croatia during the Second World War but also the centre of the resistance to nazism.
The communist government (1945) confiscated by means of "revolutionary terror" the existing companies and nationalized the remaining economy. This led, together with a massive inflow of rural population, to general stagnation.
In the 1950s cultural and scientific institutions were being gradually established: theatres (Zagreb Drama Theatre, later Gavella; Komedija Theatre), Zagreb Television (today HTV - Croatian Television, started to broadcast on 15th of May 1956), the Lexicographic Institute (1950) etc.
Despite economic and cultur al colonization between 1948 and 1990, Zagreb remained the centre of the resistance to the Yugo-communist regime ("Croatian Spring", 1971) and the focus of the cultural and national self-consciousness. Since 1991, as the capital of independent Croatia, it gradually develops into a Central European metropolis.