Criminally underappreciated Gladiator II character: Praetorian Prefect Tegula
In the Roman Empire, the Praetorian Guard was a military cornerstone of imperial rule and served a multifacated role as bodyguards to the emperors, keepers of the city, and an intelligence service whose vast power, influence, and intimate knowledge of imperial matters was often the key factor in toppling reigns and installing new rulers throughout Roman history. For emperors, winning and keeping the favour of the Praetorian Guard was a matter of life and death, and an expensive one at that, as the easiest way to keep the Guard on their good side was simply to always remain the party which paid them best.
As the highest commander in the Praetorian army, General Tegula holds one of the most powerful political positions in the whole of the Empire - but despite the Guard's dubious reputation, he leads his men with dignity, and is shown to be a moral and dutiful man whose loyalty lies not with the highest bidder, but with his people's best interest.
In real history, Septimius Severus - the father of Caracalla and Geta - began his reign by wiping clean the Praetorian slate, and installing his own loyalists as the new command and body of the Guard in order to cement his position. Though his role has been omitted from the story, it's interesting to consider the possibility that despite their obvious ineptitude, the twins may still enjoy the Guard's continued support due to their father's legacy.
Notable detail: at the end of the film, upon Tegula's concession to Lucius's command, Lucius bows his head to him with respect in grateful acknowledgement of his position and the immense importance of his gesture, which has spared Rome from a bloody civil war.