The technological period of warfare ranging from the great disaster, which brought about the Frobeolithic Glacier Epozz, to about 1000 BE is known as the Age of Barbarity. During this era, humans fought with many primative weapons, including clubs, stone axes, leather shields, leather armor, rocks, sticks, slings and other crude instruments which today would be described as tools. This age ended with the invention of metallurgy.

Age of Barbarity c. 3120~2500 to c. 1000 BE
Age of Metallurgy c. 1000 to 200 BE
Age of Archery 200 BE to 660 GUE
Age of Powder 660 to 883 GUE
Age of Kaine 883 to 949 GUE

SOURCE(S): Zork Nemesis (Game, Design Documents, Nino Ruffini's notes on the design documents)