The Snake/Personality

In the first game, the Snake is a character that cannot be trusted, turning against his former ally, the Rat and before the events of Stronghold, tricking the player's father to his death. He also, while running a province under employ of the king, under-declared some of the taxes to maximize his own profits. The Snake, however, is not cruel to his own people, as the Sheriff, with a similar personality, is. This is perhaps because his troops are weak enough as it is, and eroding their morale would make them even worse fighters. Despite his lack of cruelty, however, the Snake is less than chivalrous to opposing lords with his mocking style of taunting, drawing his sword in front of his neck in the process.
It is unknown how the Snake behaves towards his allies as there is no speech, just one of his soldiers relaying messages; however, he appears to be quite helpful to them as he is very willing to send lots of spearmen if a moat needs dug and will usually (if he is not under pressure himself) come to their aid when requested. He will also quite often enthusiastically attack an enemy when requested, and will send small raiding groups to help out in his allies' sieges even when not requested to do so. 
Finally, he is obsessed with the letter 'S', not only creating his castles in this shape but also having it as the centerpiece for his elaborate purple banner, which he proudly displays behind his throne.