History of Transylvania union of Transylvania with Romania in Alba Iulia on 1. December 1918.; Bessarabia, having declared independence from Russia in 1917 at the Conference of the Country (Sfatul Țării), called in Romanian troops to protect the province from the Bolsheviks. The union of the Transylvania, Maramureș, Crișana and Banat regions with the Old Kingdom of Romania was ratified in 1920 by the Treaty of Trianon, which recognised the sovereignty of Romania over these regions and settled the border between the Republic of Hungary and the Kingdom of Romania. The union of Bukovina and Bessarabia with Romania was ratified in 1920 by
Celts in Transylvania the River Tisa is depicted in 2nd century BC pottery found at Pecica in Arad County, a prosperous trading center at the confluence of the two peoples. A classic period of Geto-Dacian La Tène culture began in the 1st century BC centered around the city of Sarmizegetusa Regia in south-western Transylvania. Dacian king Burebista defeated the Celtic Boii and Taurisci tribes between 60–59 BC. However, some archaeological finds in Dacian settlements and fortifications feature imported Celtic vessels and others made by Dacian potters imitating Celtic prototypes. These discoveries in sites from regions north and west of Transylvania show that relations