An Etymological Dictionary of the German Language/Berg
Berg, m., ‘mountain,’ inherited from the OTeut. vocabulary; OHG. bërg, MidHG. bërc(g), m. Comp. AS. beorh(g), especially ‘barrow’ (called byrgels also), E. only in the deriv. ‘to bury’ (AS. byrgan), from *burgian; the Goth. form *bairga- is deduced from the deriv. bairgahei, ‘mountain range.’ The rules for the permutation of consonants demand a pre-Teut. bhérgho-; with this is connected Sans. bṛhant, ‘high’ (b from bh, because the aspiration at the beginning of the root was, on account of the following aspirate, necessarily lost); h is gh; Zend barezanh, ‘height,’ berezant, ‘high’; OIr. brigh, ‘mountain’ (ri, Sans. ṛ, might be compared with the ur of Burg), Armen. berj, ‘height,’ barjr, ‘high,’ W. and Armor. bre, ‘mountain, hill,’ W. bry, ‘high.’ Also the Kelt. proper names Brigiani and Brigantes, like the Teut. Burgunden, Burgundiones (lit. ‘monticulae’), and the name of the town Brigantia (Bregenz). Hence to the root bhergh belong the primary meanings ‘high, rising ground’ (OSlov. brěgŭ, ‘bank (of a river),’ is borrowed from G.); perhaps Burg is derived from this root, if it does not come from bergen. The attempt to connect Berg with Goth. fairguni and Hercynia, identical with the latter, must be abandoned. With zu Berge, ‘up, on end,’ comp. MidHG. ze tal, ‘down.’