was it also a replacement for any other model?
Leclerc tanks.
Leopard 2
The Leopard 2 first entered service in 1979, and its service life is anticipated to end around 2030. In May 2015, the German Ministry of Defence announced plans to develop a tank jointly with France as a successor to both the Leopard 2 and Leclerc tanks. 
what is referred as leopard 2e? The Leopardo 2E or Leopard 2A6E is a variant of the German Leopard 2 main battle tank, tailored to the requirements of the Spanish army,. mention any one comparison of it with other tanks? The Leopard 2A4 and Leopard 2E sport a much more powerful gun than the AMX-30 and M60 tanks. do you know when was it constructed? December 2003. and who is responsible for its construction? Germany. the main german battle tank that you mentioned earlier, when was it built? 1970s. under whom? Krauss-Maffei.
wiki:4979687
Leopard 2 [SEP] Replacement
The Leopard 2 first entered service in 1979, and its service life is anticipated to end around 2030. In May 2015, the German Ministry of Defence announced plans to develop a tank jointly with France as a successor to both the Leopard 2 and Leclerc tanks. Technologies and concepts will be investigated to determine what capabilities are needed in a future tank. Deployment of the new tank, titled Main Ground Combat System (MGCS), will be preceded by incremental upgrades to the Leopard 2, including a new digital turret core system and situational awareness system and an Active Protection System (APS).