Colonia Agrippinensis
Founded on the left bank of the Rhine by Agrippa (oppidum Ubiorum) in 38 B.C. (not 19) on a site bearing traces of Neolithic and Iron Age settlements. Later (8 B.C.? A.D. 5?) an ara Romae et Augusti was built for the future province of Germania, whence the city's name (Ara Ubiorum). Nearby was a camp for two legions, I and XX (A.D. 14; up to A.D. 9, probably XIX and XVII). Towards the end of Tiberius' reign the legions were transferred to Neuss and Bonn, but the Rhine fleet (Classis Germanica) remained near Cologne-Alteburg where its camp has been excavated. In A.D. 50 the city was made a colony (Colonia Claudia Ara Agrippinensium) at the instigation of the empress Agrippina, and acquired a city wall.
The only fortress involved in the Batavian revolt under Civilis, it was the seat of the governor of Germania Inferior, and the residence of the Gallic emperor in the 3d c. A.D., as well as a center of trade and industry (glass, pottery, goldsmiths' work, the minting of coins). In 310 Constantine erected the bridge over the Rhine with a fortified bridgehead, Divitia, on the opposite bank (now called Deutz). The city did not fall into Frankish hands until after 450; it became the residence of King Sigibert the Elder and from A.D. 507 on was part of Chlodwig's kingdom.
The site of the Roman colony in the center of the modern city has long been known, especially the city wall of the period after A.D. 50, large sections of which are still standing (a Roman tower on the NW corner and parts of the NW and S wall). Its irregular perimeter marks the limits of a natural plateau. The present-day streets correspond in large measure to the Roman ones, in particular the Hohestrasse, which lies exactly over the cardo maximus and until the 19th c. also went through the Roman N gate. The cardines are oriented directly N, but the decumani diverge several degrees to the NE, presumably in the direction that the sun rose on the birthday of the emperor Augustus.
After a peristyle house with a mosaic of Dionysus was discovered in the NE corner of the colony, at the Cathedral, further excavations revealed the entire area: streets, houses, a Mithraeum, subterranean shrines to the Matrones (indigenous female idols of mother goddess type), a temple of Mercury-Augustus, and finally the Roman and Frankish Bishop's Church beneath the cathedral. Much of these remains has been preserved below ground.
In the SW corner of the colony the capitol temple, below the church known as Maria im Kapitol, has proved to be a temple of orthodox type with its own temenos wall, built shortly after A.D. 50. The praetorium, roughly in the middle of the city's river front, lies beneath the Rathaus and may be visited. Adjoining it to the S is a large hall with a hypocaust and great apse on its long E side. This structure, which is being included in the ruins preserved underground, corresponds in size and purpose to the Palastaula (known as the Basilica) at Trier, but is ca. 100 years older (early 3d c. A.D.). The baths in the center of the city include a semicircular caldarium with a diameter of 25 m, and date from the 1st c. A.D.
The site of the Ara Ubiorum has not yet been found. The oppidum has been presumed to be close to the colony (Tac., Ann. 12.27: Agrippina . . . in oppidum Ubiorum, in quo genita erat, veteranos coloniamque deduci impetrat), but the latest excavations have shown that the two-legion camp may possibly lie under the town. Discoveries include an embankment, traces of rows of tents, and the graffito PRIN(ceps) LEG(ionis) XIX.
One monument remaining from the period of the Ubii is a high pedestal, 9 by 9 m, that originally supported a column. It may have served as a lighthouse at the harbor entrance, and is the earliest example of ashlar technique N of the Alps. In A.D. 50 it was included in the SW corner of the city wall.
Monuments outside the Roman colony that can still be seen include: the E gate of the Deutz fort (early 4th c. A.D.); the extensive excavations under the St. Severin Church; a pagan and Christian cemetery on the road to Bonn with a cemetery church that developed through various stages into the present-day basilica; the St. Ursula Church on the road to Neuss, originally a cemetery basilica with 11 loculi; the St. Gereon Church in the NW part of the city, whose late Roman core can still be seen but which apparently goes back not to the time of Constantine but to that of his sons; and finally, W of Cologne on the Roman road to Jülich, the Weiden burial chamber containing a sarcophagus and busts of the deceased persons.
BIBLIOGRAPHYR. Schultze et al., “Colonia Agrippinensis,” BonnJbb 98 (1895); 1. Klinkenberg, Das römische Köln, Die Kunstdenkmäler der Stadt Köln 2 vols. (1906); id., “Die Stadtanlage des römischen Köln und die Limitation des Ubierlandes,” BonnJbb 140-41 (1936) 259ff; F. Fremersdorf, “Neue Beiträge zur Topographie des römischen Köln,” Romisch-Germanische Forschungen (RGKomm) 18 (1950); O. Doppelfeld, “Das Praetorium unter dem Kölner Rathaus,” Neue Ausgrabungen in Deutschland (1958) 313ff; id., “Die Ausgrabung unter dem Kölner Dom,” ibid. 322ff; id., ed., Römer am Rhein, Ausstellungskatalog (1967); Rom am Dom Ausstellungskatalog (1970); P. La Baume, Colonia Agrippinensis (1965).
O. DOPPELFELD