Celts in Transylvania arrived in northwestern Transylvania in around 400–350 BC as part of their great migration eastwards. When Celtic warriors first penetrated these territories, the group seem to have merged with the domestic population of early Dacians and assimilated many Hallstatt cultural traditions. The second half of the 4th century BC saw the Middle La Tène Celtic culture emerge in north-western and central Dacia, a development reflected especially in burials of the period. Celtic artifacts dating to this time have been discovered at Turdaş, Haţeg and Mediaş in modern-day Romania. By 1976, the number of Celtic sites found in Transylvania had reached
Transylvania to Transylvania, and 280,000 from Transylvania to the Old Kingdom, most notably to Bucharest). According to the results of the 2011 Population Census, the total population of Transylvania was 6,789,250 inhabitants and the ethnic groups were: Romanians - 70.62%, Hungarians - 17.92%, Roma - 3.99%, Ukrainians - 0.63%, Germans - 0.49%, other - 0.77%. Some 378,298 inhabitants (5.58%) have not declared their ethnicity. The presented data are from http://www.recensamantromania.ro/rezultate-2, the Table no. 7. The ethnic Hungarian population of Transylvania form a majority in the counties of Covasna (73.6%) and Harghita (84.8%). The Hungarians are also numerous in the following counties: