Helmstedt (hĕlmˈshtĕt) [key], city (1994 pop. 26,700), Lower Saxony, N central Germany. Manufactures include bricks, lignite, machinery, and yarn. Helmstedt was founded in the 9th cent. and later (15th–16th cent.) was a member of the Hanseatic League. From 1576 to 1810 it was the seat of a noted university, whose Renaissance-style buildings still stand. From 1945 until German reunification in 1990, Helmstedt was a major frontier post between East and West Germany.