Brian Aherne received his only Oscar nomination for portraying Emperor Maximilian Von Hapsburg in Juarez.
Brian Aherne portrays the appointed Emperor of Mexico. This might actually be first circumstance of category misplacement, since Aherne really is the co-lead of the film along with Paul Muni who portrays Juarez. Although he is basically a pawn of Napoleon Emperor of France (Claude Rains), Maximilian takes his position seriously though, and does show genuine concern for the Mexican people, even if he does not fully understand the situation he has found himself in.
Aherne actually does a fine job of combining the naive nature of the character well, with the genuine earnestness in what he believes is right as well. He does not make Maximilian stupid instead showing really that the whole idea of leadership of Mexico really is something he should never been in place for, and his earnestness is not made out to be overly heroic by Aherne, but rather just a really a rather normal man attempting to do what he believes to be the descent thing to do.
For about the first three thirds of the film Aherne stays consistent in this fashion, except for a brief moment where he allows cruelty toward the supporters of Juarez. Aherne makes this moment believable because he shows the emotion of the attack near his family just really struck him in the wrong fashion, allowing the feeling to overcome him. Aherne is never really amazing, but he certianly is consistently fine as the Emperor up until near the end of the film.
Now many times in these sorts of performances is where I would become negative, because many times the actor fails to meet the challenging parts of the performance, luckily though Aherne actually improves at the end of the film. Aherne has a few genuinely moving, and heartfelt moments at the end of the film, where Maximilian refuses to forget his duty to the Mexican people he believes he has even though his wife (Bette Davis) has become mentally ill.
When Maximilian must see his fate through well remembering his time with his wife, Aherne manages to bring the emotions outward effectively particularly through two small but moving reactions near the end of the film. One when he reflects about a dream about his wife where he shows a genuine love for his wife, although combined with a sense of duty that keeps him away from her, and finally his best moment when he is going to be taken to be executed Aherne's heartbreaking reaction when Maximilian hears a song that reminds him of better times. Except for that scene which alone almost brought him to a four, this is not an amazing performance, but it is most certianly a fine one.