Saldae was an important port city  in the ancient Roman Empire, located at today's Béjaïa (in eastern Algeria). It was generally a crossroads between eastern and western segments of Northern Africa, from the time of Carthage to the disappearance of the Eastern Roman Empire from the continent.
The Roman period has left more abundant remains. Vestiges of the ramparts are visible at several places....Of the monuments which have been preserved or noted, particularly interesting are the remains of a temple underneath the church, built on the site of a mosque. The temple was undoubtedly near the forum, whose location is indicated by the bases of statues. In the immediate vicinity the public baths have produced a large ornamental mosaic (a piece of it is on exhibit in the church). Other public baths were on the site of the Civil Hospital. Two similar mosaics were found there; they depict heads of Oceanus flanked by Nereids. One is at the Algiers Museum, the other at the town hall of Bejaia. A third public bath was located near the high school.Cisterns and basins are still visible (indeed, still in use) at several places in the upper town. They were fed by the Toudja aqueduct, which brought water from springs located 21 km to the West....West of the middle town a rounded depression has been supposed variously to have been the site of a circus, an amphitheater, and a theater. No ancient remains are known that settle the question. A single inscription (CIL, VIII, 8938) mentions "ludi circenses".Many Roman sculptures have been found in the area around the town, some carved in the rock, some found in the ground, others as sarcophagi. A sarcophagus with strigils is at the Louvre. Few sculptures come from Saldae itself, mainly some capitals and votive stelae dedicated to Saturn.Perseus 
The city grew in size with new buildings and the emperor Vespasian settled the city with many Roman veterans, increasing its population and importance in the province of Mauretania Caesariensis, later in the fraction "Sitifensis". It eventually became part of the province to the East, Mauretania Sitifensis.
The city was under the roman ius and their citizens were endowed with full civil rights. Saldae was a center of a Mauretania Caesariensis area fully Romanised, that in the late third century was even fully Christian.
In the third century AD, Gaius Cornelius Peregrinus, a Decurion (town councillor) from Saldae was a Tribunus (military commander) of the auxiliary garrison at Alauna Carvetiorum in northern Britain. An altar dedicated to him was discovered shortly before 1587 in the north-west corner of the fort, where it had probably been re-used in a late-Roman building ().
Conquered by the Vandal Kingdom in 429 AD, Saldae remained a key stronghold. That kingdom fell a century later, conquered by the Byzantines' empire, who established an African Prefecture, and later the Exarchate of Carthage.
Christianity was worshipped in Saldae since Trajan times, and later Saldae was a Dioceses. In 484 AD the Bishop Pascasius participated in the Carthago Sinodus. Furthermore, Christianity survived the Arab conquest that happened in the seventh century: Pope Gregorius VII in the XI century wrote a letter Clero et populo Buzee, about the nomination of bishop Servandus for Christian north Africa.
Saldae had nearly disappeared by the end of the first millennium, but was refounded as "Béjaïa" by the Berber Hammadid dynasty (whose capital it became) in the 11th century, and became an important port and cultural center. As a principal town of the Hammadid leader, Emir En Nasser, Béjaïa flourished and was renamed En Nassria.
The son of a Pisan merchant (and probably consul), posthumously known as Leopoldo Fibonacci, in this city learned under the Almohad dynasty about Indian mathematics which he called "Modus Indorum" (Hindu-Arabic numerals) and introduced them and modern mathematics into feudal Europe with his book Liber Abaci: it was part of the introduction of Islamic and Classical knowledge that helped spur the Renaissance, lifting Christendom out of the Dark Ages.
- Saldae (in Italian)
- Pliny the Elder: Natural History
"Rusazus, a colony of Augustus, Saldae, a colony of the same, Igilgili likewise; the town of Zucca, situated on the sea and the river Ampsaga."
- Perseus: Saldae
- Dictionary of Greek and Roman Geography:
"In later times it was the western limit of Mauretania Sitifensis, against Mauretania Caesariensis in its more contracted sense."
- En Nasser's son, el Mansour, built an impressive palace inside the fortifications constructed by his father over Roman buildings. The Hammadid Empire fell in 1152, when the Almohad ruler, Abd al-Mu'min, invaded central Maghreb from Morocco (Geoff Crowther & Hugh Finlay, p. 292)
- Geoff Crowther & Hugh Finlay. Béjaïa & the Corniche Kabyle, Morocco, Algeria & Tunisia: a travel survival kit. Lonely Planet, 2nd Edition, April 1992
- Serge Lancel et Omar Daoud. L'Algérie antique : De Massinissa à Saint Augustin. Place des Victoires, 2008 (ISBN 9782844591913)
- Mommsen, Theodore. The Provinces of the Roman Empire Section: Roman Africa. (Leipzig 1865; London 1866; London: Macmillan 1909; reprint New York 1996) Barnes & Noble. New York, 1996
- Reynell Morell, John. Algeria: The Topography and History, Political, Social, and Natural, of French Africa. Publisher N. Cooke. London, 1854 ( )