Câmpulung (also spelled Cîmpulung, Romanian pronunciation: [kɨmpuˈluŋɡ], German: Langenau, Old Romanian Dlăgopole, Длъгополе (from Middle Bulgarian), or Câmpulung Muscel) is a city in Argeș County, Muntenia, Romania. It is attested on the Fra Mauro map from 1450 as Campo longo. It is situated among the outlying hills of the Southern Carpathians, at the head of a long well-wooded glen traversed by the river Târgului, a tributary of the river Argeș.

Near Câmpulung are the remains of Jidava (or Jidova) Roman fort built around 190–211 AD on the frontier of the empire, the Limes Transalutanus; and just next to it, vestiges of a Roman colony, variously identified with Romula, Stepenium, and Ulpia Traiana. Now called Grădiștea (meaning place of a fortress in Romanian) or Jidovi.

Campulung was also important because it was only 37 km (23 mi) away from the Bran Pass, an important trade and military route for militaries and merchants.

Câmpulung was the first capital of the feudal state of Wallachia which might mean that the city might have been built in the 13th century, until succeeded by Curtea de Argeș in the 14th century. There was a considerable traffic with Transylvania, over the Rucăr–Bran Pass, 24 km (15 mi) to the north, and with the south by a branch railway to Ploiești.

Câmpulung was one of the earliest urban settlements in Wallachia, the Transylvanian Saxon colonists contributing to its development by bringing the German urban culture. The earliest written evidence of the town's existence is dated 1300, and is to be found in the Câmpulung church. The inscription is an epitaph of Laurencius de Longo Campo, the full text being Hic sepultus est comes Laurencius de Longo-Campo, pie memorie, Anno Domini MCCC ("Here is buried count Laurentius of Longus-Campus, in pious memory, Anno Domini 1300"). Laurentius was most likely the person coordinating the colonization process.

The oldest known written document in Old Romanian was dated back to 1521 (Neacșu's letter). The letter was written to warn the city of Brașov of an impending Ottoman attack. The letter, written in Old Romanian, names the city in the introductory part written in Old Church Slavonic as Dlăgopole — Длъгополь (with the same meaning — "a long field").

When the printing press started to get popular in Europe, Matei Basarab managed to bring a printing press in Câmpulung in 1635 where Orthodox books would be printed and would be sent all over the Balkan peninsula for Orthodox people. This did not last long and in 1650 there weren't records of books being printed after that.

During the reign of Șerban Cantacuzino (1678–1688), pressure was exerted to change the Catholic judges of Câmpulung to Eastern Orthodox.