Kikou Sennyo Rouran (2002)

Dr. Masahiko Mikogami created the organization ASY, & it’s five mechs called Gousens, to act as the new defense force for Japan after it’s own military joined the UN. ASY immediately went after the Shiromorishu, a mysterious group that guided Japan spiritually for centuries, stating that the group had been controlling Japan instead of guiding it. Though their base has been destroyed & their successor, Tatsuya Takechi, is gone & possibly dead the Shiromorishu are ready to enact their vengeance on ASY... But a mysterious girl named Rouran will complicate matters further by bringing back the past between Mikogami & the Shiromorishu.

Source: www.anisearch.com/anime/1058