As the level of difficulty goes up, so does the number of citizens born unhappy. Part of the challenge of the higher difficulties is dealing with unhappiness.
You can deal with unhappiness at the beginning with either Military Police (warrior in city), by using the luxury slider, or by creating entertainers (pulling people off working tiles).
You can deal with unhappiness at the beginning with either Military Police (warrior in city), by using the luxury slider, or by creating entertainers (pulling people off working tiles).