Map - Beyoğlu

Beyoğlu (, بك‌اوغلی) is a district on the European side of İstanbul, Turkey, separated from the old city (historic peninsula of Constantinople) by the Golden Horn. It was known as the region of Pera (Πέρα, meaning "Beyond" in Greek) surrounding the ancient coastal town Galata which faced Constantinople across the Horn. Beyoğlu continued to be named Pera during the Middle Ages and, in western languages, into the early 20th century.

According to the prevailing theory, the Turkish name of Pera, Beyoğlu, is a modification by folk etymology of the Venetian title of Bailo, whose mansion was the grandest structure in this quarter. The informal Turkish-language title Bey Oğlu (literally Son of a Bey) was originally used by the Ottoman Turks to describe Lodovico Gritti, Istanbul-born son of Andrea Gritti, who was the Venetian Bailo of Constantinople during the reign of Sultan Bayezid II (r. 1481–1512) and was later elected Doge of Venice in 1523. Bey Oğlu thus referred to Lodovico Gritti, who established close relations with the Sublime Porte, and whose mansion was near the present-day Taksim Square. Located further south in Beyoğlu and originally built in the early 16th century, the "Venetian Palace" was the seat of the Bailo. The original palace building was replaced by the existing one in 1781, which later became the Italian Embassy following Italian unification in 1861, and the Italian Consulate in 1923, when Ankara became the capital of the Republic of Turkey.

The district encompasses other neighborhoods located north of the Golden Horn, including Galata (the medieval Genoese citadel from which Beyoğlu itself originated, which is today known as Karaköy), Tophane, Cihangir, Şişhane, Tepebaşı, Tarlabaşı, Dolapdere and Kasımpaşa, and is connected to the old city center across the Golden Horn through the Galata Bridge, Atatürk Bridge and Golden Horn Metro Bridge. Beyoğlu is the most active art, entertainment and nightlife centre of Istanbul.

The area now known as Beyoğlu has been inhabited since Byzas founded the City of Byzantium in the 7th century BC, and predates the founding of Constantinople. During the Byzantine era, Greek speaking inhabitants named the hillside covered with orchards Sykai (The Fig Orchard), or Peran en Sykais (The Fig Field on the Other Side), referring to the "other side" of the Golden Horn. As the Byzantine Empire grew, so did Constantinople and its environs. The northern side of the Golden Horn became built up as a suburb of Byzantium as early as the 5th century. In this period the area began to be called Galata, and Emperor Theodosius II (reigned 402–450) built a fortress. The Greeks believe that the name comes either from galatas (meaning "milkman"), as the area was used by shepherds in the early medieval period, or from the word Galatai (meaning "Gauls"), as the Celtic tribe of Gauls were thought to have camped here during the Hellenistic period before settling into Galatia in central Anatolia, becoming known as the Galatians. The inhabitants of Galatia are famous for the Epistle to the Galatians and the Dying Galatian statue. The name may have also derived from the Italian word Calata, meaning "downward slope", as Galata, formerly a colony of the Republic of Genoa between 1273 and 1453, stands on a hilltop that goes downwards to the sea.