On the lands of Bihor the appearance of man can be dated back to the end of Middle Palaeolithic (about 50 000 – 35 000 B.C.). The discovery in 1909 in the perimeter of the former brick yard Knapp (close to the current railway station Oradea East) of a deposit of bones made up of 17 items belonging to various species of animals strengthened in many researchers the belief that they represent household remains dating back to Superior Palaeolithic, confirming the presence of Homo sapiens since then on the current territory of Oradea.
Even if for Epipaleolithic and Mesolithic (about 10 000 – 5 500 B.C.) there are no certain discoveries on the radius of the city, it is assumed there was no hiatus between Palaeolithic and Neolithic.
The Neolithic or carved stone age (6 400/5 500 – 2 500/2 200 B.C.), characterized by the appearance of stable human settlements, is represented for the history of Oradea by several cultures (some of them extended to the whole country), such as the culture Criş (Superior Neolithic), Ciumeşti and Tisa (in North-West, Middle Neolithic), Tisa III (Tiszapolgár), Gheja, Coţofeni, Baden (Superior Neolithic). In the perimeter of Oradea Neolithic settlements were examined in several points: on the terrace Salca, in the points Guttmann, Gheţărie, Rulikowszky Municipal Cemetery, Seleuş, Petöfi Park.
Ceramic fragments belonging to this period discovered on the occasion of archaeological diggings belong to vessels of different shape and sizes; pots with arched walls, bowls with small legs, vessels with profiled bottom or with short leg, cups with thin walls etc. As for houses, so far two categories were discovered: cottage type (actually inhabitable pits of oval shape with a hearth placed directly on the clay floor) and platform houses, of surface. The practise of agriculture in this period is confirmed by the discoveries from Oradea-Salca of many grubbing hoes of stag horns, hand mills, carbonized wheat beans (Trititicum monococcum L) or bones of certain species of animals such as the goat (capra hircus) and the ox (bos taurus).
The period of transition from Neolithic to Bronze Age: stretches over seven centuries and is represented in Oradea by three great cultures: Gheja-Bodrogkersztúr, Coțofeni and Baden. The ceramics of these cultures is especially represented by vessels shaped like “flower pots” and “milk can”, bowls with flat bottom, cups with spherical or ovoid body, bowls in the shape of a truncated cone, amphorae, different types of cups etc.
Bronze Age: (about 2 200 – 1 200/1150 B.C.): was investigated in several settlements from the plateau Salca, on Dealul Viilor, in front of the Tuberculosis Sanatorium, near the current municipal stadium etc. The most representative of the cultures in the area of Crișurilor Basin was the culture Otomani, to which added the cultures Wittenberg, Suciu de Sus, Periam-Pecica. With a very rich ceramic material, on the occasion of archaeological diggings many bone tools were revealed (planting machines, grubbing hoes, coulters etc), bronze parts and ornaments.
Iron Age: represents the last stage of evolution of primitive society and is divided in two: the first Iron Age called Hallstatt and the second Iron Age called La Téne. Apart from ceramics in the first part of the period a significant importance had the discoveries of bronze weapons (swords, daggers), treasures of gold objects (at the beginning of 20th century there were already three of them known), vestiges of settlements etc. In parallel appeared the first iron tools (since early Hallstatt), the oldest ones on the territory of Oradea were a number of several Celts. In time there were added different harness pieces, weapons, agricultural tools, vessels, ornaments. Iron Age also coincides with the appearance of the first written information about Dacian Geta owing to the “Father of History”, Herodotus, the moment represented the passage from prehistory to history. It also coincides with the penetration of Celts to Central Europe, this vast process had some of the deepest consequences on the history of Romanian area, the Celts being known as good farmers who used the plough with iron coulter and three-year rotation. Celtic discoveries were made in Oradea in the place called Pusta Iklod, on the plateau Salca, in the area of municipal stadium etc. Towards the end of the age it could be noticed a marked increase of monetary circulation, along with late Celtic coins also circulated Dacian imitations after Greek and Macedonian coins.
Ancient Times: Dacian civilization in Oradea area integrated in this period by its characteristics in the general framework of Dacian civilization across its whole expansion. In Oradea Dacian settlements were investigated at Oradea-Salca II, on Dealul Viilor, Oradea-Sere, Ioșia, Seleuș. The Roman conquest after the two wars with Dacians did not include the North-West of Romania or the region of Oradea, although some historians claimed so at a certain moment, identifying in parallel Oradea with the hypothetical city Ulpianum. Free Dacians (that part of Dacian population which remained outside the Roman Empire) from the current territory of the city or in its neighbourhood continued to live in their old settlements, very few of those from the lower stream of Crișul Repede River disappeared at the beginning of 2nd century A.D. The archaeological discoveries belonging to free Dacians from Oradea area are relatively few, which explains the especially small number of archaeological diggings made for this purpose. The existing ones demonstrate certain influences coming both from Sarmatian tribes in the near vicinity and Roman influences. We could also see an intense circulation of Roman imperial coins which cover from chronological point of view the II-III centuries A.D.. The coins which circulated in Oradea were especially issued during the reign of Traian (96-117 A.D.), Hadrian (117-138 A.D.) and Antonius Pius (147-161 A.D.). In fact, during the period of Roman reign over Dacia the relationships between free Dacians and Imperials were peaceful, being most often carried out at economic level. After the Aurelian withdrawal and the leaving of Dacia by the Empire (271 A.D.) the monetary circulation began to decrease, but without disappearing completely.
The period of transition from ancient times to Middle Ages: stretches from the moment of leaving of Dacia by the Roman authorities until the appearance of the first pre-state formations at the beginning of 5th century A.D. The stage of current research indicates for this moment an effervescent, transitory period characterized by a series of historical processes which were based on Dacian Roman population. The Aurelian withdrawal did not affect the ethnic structure of the areas inhabited by Dacians, so we can speak with certainty of a continuity of habitation of the natives, in case of Oradea proven by the discoveries from Oradea – Salca. A new element will be constituted by the succession of several waves of migrants which will leave deep marks on the life of inhabitants. At the beginning it was noted the presence of Ostrogoths, Huns and Ostrogoths, the discoveries belonged to the latter from Oradea area and were classified from chronological point of view in the 4-5th centuries A.D. The Hun reign expanded during Attila over a large part of Pannonia Plain will be defeated by Gepids in 454, who also exerted dominance over Crișana. In 568 their power will be defeated by Avars. Even if so far there are no certain materials discovered in Oradea and belonging to the newcomers, it is assumed that they controlled the current surrounding area of the city. They were followed by Slavs, whose safe presence in Oradea area can be established with approximation at the end of 7th century (after 680). The symbiosis of local population with Slavs is documented by the appearance in a series of Avar settlements or necropoles (from the whole Transylvania) of ceramics worked on fast wheel, generalized through them. After the massive passage of Slavs to the south of Danube after the disappearance of Byzantine power from there, the Dacian Roman population will assimilate the Slavian enclaves left north of the great river.