Two men, antithetical in attitudes, philosophies, and even talents, have joined the same army, with the same intention: rise through the ranks, and lead it to victory against the cruel man who calls himself their emperor, whose transgressions against his subjects finally have grown too great to ignore.
{A} is a smith, or a carpenter, or a man of any other craft which you may prefer. He is too old to be drafted, but his apprentice wasn't, so the boy was dragged away to fight in the tyrant's army. That was many months ago. Now the man cannot keep his shop afloat by himself, so he does what his conscience tells him to do: craft a spear, a shield, and a mail shirt for himself. Sell the tools and the excess metal and use the money on food and other supplies. Then volunteer. If he joins then that's another smith's apprentice somewhere who can stay in his village and continue learning his trade. Besides, if {A}'s contributions to the war effort will end the war even ten minutes sooner, that's all the sooner that the survivors can go home, and carry on with their lives.
{B} is different. The son of a priest, or perhaps a magistrate, he was raised to value humility above all things. He owns no property and no possessions, not even the monastery's itchy robes which cover his beautiful body (as if it were something to be ashamed of—the tragedy of it!). He's sick of it; serving the diseased, the lazy, the poor, the ungrateful! He deserves so much better, which he knows deep in his heart. The war is his opportunity to seize something for himself at last; something he can own, and wear, and love, which he will never have to give away to others less fortunate than he. And what better gift to give himself than a crown?
Liberators. Heroes. One man has joined this army because he agrees with their ideals, and desires for the realm the same brand of justice as they. Another has joined because they have an army; and he has decided that it will be easier to defeat the king in battle than to get close to him, stab him in the back, and somehow come out of that treachery with a crown and a throne. Both learn that they have a great talent for leadership, when given the proper resources and training to survive their first battles. They are allies; but does that mean they are able to be friends? Shall they only use each other as pawns, or can they come to a common understanding as to the meaning of the war, and the tragedies it composes from the flesh of the dead?