He was named after Gustav Husak.
Unlike his wife Gustav has red fur with a white underbelly like virtually any normal fox or most of the colour scheme that most of the generals and the soldiers in the Junta have. In his first appearance he is a normal fox but in his return in the Anthro Saga he wears a white shirt, a grey marshall jacket and grey trousers in general but in Argentina he wears a grey suit.
Gustav is a highly experienced leader and though he is a very serious character alongside his wife Ivana she is more laid back than he is however he is not entirely as strict as Ante, Heriberto or Hugo but is not very laid back either. Much like his wife he has a relatively dry sense of humour but although he does not wish to sing for the concert organized by the Junta he does it anyway and proves to be good with it. Alexander also says that much like Kim il Sung he has a great presece among his allies but he is not exactly Slim from Of Mice and Men as he considers that if he was that would be too over the top.
Another Czech general Vaclav also says there is a great sense of mystery around Gustav much like with the Mexican general Gregorio and the Hungarian fox Tibor as well as many members of the Animalian Patriotic Front. Towards his allies and eventually enemies he is very chivalrous mainly towards females in both organizations of his allies. He is also respectful to Brainy Barker when he first meets her as well as very good with the Junta babies being one of the generals who does not intimidate or scare them, but as well as Josefina, Santiago and Guillermo since he is a baby when his father shows him around the Bunker but the general is also good with it's sole kitten Valerie. Aside his flaws though he does love his wife and son.