Metaltech: Earthsiege is a mecha-style simulation game developed by Dynamix and released in 1994. Earthsiege is the first in a long line of games set in the same universe which include: Battledrome (1995), Earthsiege 2 (1995), Cyberstorm (1997), Cyberstorm 2 (1998), Starsiege (1999), Starsiege: Tribes (1999), Tribes 2 (2001), and Tribes: Vengeance (2004).
In Earthsiege, players are placed in the cockpit of various massive bipedal war machines known as HERCULANs (Humaniform-Emulation Roboticized Combat Unit with Leg-Articulated Navigation) (or 'HERCs' for short). Set in the 25th or 26th century, Earthsiege is a technologically advanced setting with many futuristic weapons and vehicles. Earthsiege takes place across North America, South America, Antarctica, and Asia.
Source: Wikipedia, "Metaltech: Earthsiege", available under the CC-BY-SA License.