Dictionary of Medieval Names
from European Sources

Theodehard m. Gothic þiuda 'people, folk' + Old Saxon hard, Old High German hart 'strong, hard'.

France
Latin
c823 Teudhardus (nom) irminon-vol2 30, Gaugiacum, Teuthardus (nom) ibid. 87, Palatiolum; 969 Tiddardi (gen) CartSavII 4; c1000 Teotardus (nom) ibid. 172, Teothardi (gen) ibid. 172, Teothardus (nom) ibid. 172
Germany
Latin
822x875 Thiadhardus (nom) TradCorb §66; 948 Thidardo (abl) HambUrk-vol1 XXXV; 1216 Dithardus (nom) hennes-vol1 22; 1259 Tethardus (nom) CDL-1.1.1 XXXI
Latvia
Latin
1299 Dethardus (nom) RigSB 88; 1300 Dethardo (dat) ibid. 420; 1301 Dethardus (nom) ibid. 311; 1302 Dethardo (dat) ibid. 192; 1303 Dethardi (gen) ibid. 373, Dethardo (dat) ibid. 373, Dethardus (nom) ibid. 96; 1304 Dethardo (dat) ibid. 200; 1307 Dethardo (dat) ibid. 109, Dithardus (nom) ibid. 107; 1317 Dethardo (dat) ibid. 319; 1319 Dethardo (dat) ibid. 114, Dethardus (nom) ibid. 320; 1333 Dethardus (nom) ibid. 321
Poland
Latin
1251 Dithardus (nom) hennes-vol1 141
Cite as: S.L. Uckelman. "Theodehard". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2017, no. 1. http://dmnes.org/2017/1/name/Theodehard.