Gaziantep is probably the site of the Hellenistic city of Antiochia ad Taurum ("Antiochia in the Taurus Mountains"). A few km to the north are the ruins of Greek and Roman Doliche (Turkish: Dülük).
Gaziantep is one of the most developed provinces of the region and is also one of the oldest, its history reaching as far back as the Hittites. Being the center of pistachio nut cultivation in Turkey and with its extensive olive groves and vineyards, Gaziantep is one of the important agricultural and industrial centres of Turkey.
In the center of the city stands the Gaziantep Fortress and the Ravanda citadel as the reminders of past. The Archaeological Museum, with its important collections from Neolithic and the Hittite ages as well as the Roman and Commagene times, attracts many visitors. The surroundings of the city are also full of valuable Hittite remains. The Hasan Süzer House, which has been restored to its original beauty, now houses the Ethnographical Museum. The Yesemek Sculpture Workshop, 30 kilometers south of the town of Islahiye, is one of the world's first of this kind. Some of the other historical remains are the Belkis (Zeugma), and Kargamış Ruins. Dülük, which is close to the city center, has camping facilities in a natural setting.
In the Ottoman period, Aintab was in the eyalet of Aleppo (vilayet after 1864).
According to the Ottoman census of 1543, the Aintab subdivision of the governorate-general of Aleppo contained fifteen tribes, all Turkmen. Much of the Aintab elite was also of Turkmen origin. There is no cadastral evidence of Kurdish tribes with administrative ties to Aintab officialdom. According to a recent study of the Aintab courts, this could partially be explained by the tributary Reklam_link Kurds of the broader region had negotiated with the Ottomans. In the same period, Aintab's demographic makeup stood out from the rest of Aleppo province or other surrounding provinces, since its non-Muslim population was relatively small and uniformly Armenian Christian, while the neighboring governorate-general of Dulkadir (Maraş) was approximately 4,5% non-Muslim and that of Diyarbakır was approximately 15 per cent. Aintab appears to have had no Jewish community, although a Jewish financier, most probably based in Aleppo, figured prominently in the city's economic and administrative life.
By the end of the 19th century, it had a population of about 45,000, 2/3 of which was Muslim, largely Yörük Turkmen of the Çapanoğlu clan.
Of the Christians, the majority were Armenian. The Gregorian Armenians suffered from the massacres of 1895, but the Armenian Protestants thrived, drawn by the American Mission Board's Central Turkey College. There was a sizable Armenian population in the city before World War I.
Gaziantep is famous for its regional specialties: the copper-ware products and "yemeni" slippers, specific to the region, are two examples. The city is an economical center of South Eastern and Eastern Turkey. The number of large industry businesses established in Gaziantep comprise four percent of the Turkish industry in general, and small industries comprise six percent. Also Gaziantep has the largest organized industrial area in Turkey and holds first position export and import goods Gaziantep also has a developing tourist industry. Development around the base of the castle upgrades the beauty and accessibility to the castle and to the surrounding copper workshops. New restaurants and tourist friendly businesses are moving into the area. Tourists are still a novelty in Gaziantep and the locals make them very welcome. Many of the students studying English language are willing to be guides for tourists.
Gaziantep is one of the leading producers of machined carpets in the world. It exported approximately $700 million USD of machine-made carpets in 2006. There are over 100 carpet facilities in the Gaziantep Organized Industrial Zone.
Gaziantep also produced 60,000 MT of pistachios in 2007. Turkey is third in pistachio production in the world, after Iran and USA.
Gaziantep is well-known for its culinary specialties, which show Arabic and Assyrian in addition to Turkish, influences. The festive food yuvalama (rice and meat rolled into pea-sized balls), the delicious lahmacun (also known as Turkish pizza) and baklava are some examples.
Gaziantep Anatolian High School (founded in 1976) is a public school focusing on English language education.
Gaziantep Science High School is a public boarding high school in Gaziantep, Turkey with a curriculum concentrating on natural sciences and mathematics, and with teaching in Turkish and English.
The main campus of Gaziantep University is located 10 kilometers away from the city center. The institution acquired state university Reklam_link in 1987, but had already offered higher education since 1973 as an extension campus of the Middle East Technical University.