Zurich has been consistently settled since the Roman Empire, though humans have lived in the area since prehistoric times. The first historical reference is from 15BC, when a military base was established. The nearby town was called Turicum. Little is known about Zurich's history throughout the early middle ages. The area was controlled by a succession of Germanic tribes.
In 853AD, Ludwig the German built a convent overtop the graves of Zurich's patron saints, Felix and Regula. The convent quickly rose in importance and in 1045 was granted the right to hold markets by the Holy Roman Emperor. By the start of the thirteenth century, Zurich became an important economic center. Zurich became a free city in 1218 and the city walls were built in the 1230s. The power of the convent began tow wane, being overtaken by the new town.
Zurich became a part of the Swiss Confederation in 1351. It continued to grow and became a center of trade and money lending. By the mid-fifteenth century, Zurich began to get close with Hapsburg Austria. The rest of the Swiss Confederacy did not approve, leading to the Old Zurich War, which lasted from 1440-46. Zurich persevered, but remained part of the Confederacy. The war proved to be a major setback to the city's economy, which began to turn inward.
It was not until the mid-seventeenth century when Zurich regained its economic importance. A spectacular new set of city walls were built in 1642 during the Thirty Years' War, and in 1648 Zurich became a Republic. The city continued to thrive in relative peace as a center of trade and commerce. That continued until the French Revolution and the Napoleonic Wars, when Zurich was reabsorbed into Switzerland. Turmoil continued until the creation of the modern Swiss Confederation in 1848.
Though it was not the capital, the new stability allowed Zurich to regain its economic importance. As industrialization began, the city once again became a center of banking and commerce. Grand new civic projects, such as the railroad and new boulevards, were constructed. It was also home to the Swiss stock exchange. Because of Switzerland's neutrality, Zurich was largely spared the carnage of the world wars. The population peaked at close to half a million around 1950, though in recent years many have moved from the urban core to the suburbs. Zurich remains a pleasant and highly livable city, and also an epicenter of global finance.