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Grand Duke Herbert (archival image)
Herbert (Japanese: ヘルベルト) was a grand duke and the 3rd son of Friedrich III who led the Imperial fleet in its first battle against the Free Planets Alliance, at the Battle of Dagon in 640 UC (331 IC / 3440 CE). Although the fleet he commanded was quite large, it was soundly defeated by an Alliance fleet half its size.
Grand Duke Herbert led an Imperial Fleet in the first attempted invasion of the Free Planets Alliance at the command of Kaiser Friedrich III. His fleet was soundly defeated by the Supreme Commander of the Alliance Fleet, Lin Pao, and though Grand Duke Herbert survived and escaped, he was placed under house arrest and psychiatric treatment afterwards. This battle marked the begining of the Alliance–Imperial War.