In first time meetings between Europeans and other people unknown to the Europeans at that time, the first ones were marked by bloodshed. For Example, the first meeting between the Norse (for you uneducated people out there, the Vikings- but these guys right here are the more peaceful side) and the Inuit (Native American tribe that spread to Greenland) ended with the Norse attacking and killing the Inuits they met, because of the advantage of the Norse having iron weapons and armor. But why did they attack? Besides all ready being predjudiced against them (the Norse, when they first aw evidence of other peoples, termed them skraelings, which meams wretches)? Because first encounter scenarios are simply scary. It is not a matter of simply walking up to the unknown culture, shout hello, and start using sign language. During them, the other culture perceives that this stranger may be a threat to them, and hurt their people. Each side is carefully watching to make sure that the enemy isn't going to start attacking, because you know you're ready to start fighting. Neither side knows the other's language, so you can't simply say that you don't want to fight, or anything like that. With the Norse-Inuit, this was the first European-native american encounter. The Norse had no experience of first encounters, nor did they have written accounts telling them what to do. Europeans would eventually develop those texts, so that they could set the groundwork during that first encounter for later exploitation. In modern first encounters (with unknown tribes in the Amazon, New Guinea, etc), the situation is still very scary, even though the modern people have guns, and hundreds of years of such experience.
When this is applied to the FRPG, make the above true. If this is the very first first encounter, then it should develop into combat. Unless one side has very, very high charisma score, then their should be no dice rolling for if their going to fight. Only dicing rolling for the when. If one does have a very high charisma roll, then I would give it a 1-5% of no fighting (assuming the person with the charisma doesn't want to fight). If the PCs do want to fight, then feel free to make the nations they inadvertantly represent, who might just want good trade relations with the new culture(s), not like them (and just maybe hand them over to the new culture they just upset...). And even later, if the PCs survive a few first encounter situations, or have read a book on them, make sure there's a chance of the meeting end in bloodshed. After all, the other culture might just think with their axes...
Cast of Characters
Religon: They believe that people are all members of a hive, like bees. But in ages past, the god of chaos decided to destroy the harmony of the peoples living in order and perfection under their Queen (who's a goddess). And so the god of chaos, after tricking the Queen into leaving, closed off the portion of the human mind that allowed the entire hive of humans to be a hive. Things would have been fine afterwards, since the Queen (when she came back) would have turned it back on, if the god of chaos then handed a small group of humans, who lacked food, clubs, and told them that other humans had food. And thus the first war took place. When the Queen returned, she mourned each humans passing, and thus, for the rest of eternity, humans attempted to achieve an impossible peace.
Outlook: Peaceful, but prepared for war, since bandit tribes rove to take the food from the farming tribes (like the Snugladuuc).
They consist of a fighter (who's the leader. He'd rather have peace than violence), a cleric (who's ordered by his god to convert the new tribes previously unknown, that were living on the other side of the Wall Mounts), a thief/rogue (interested in the money), a wizard (who thinks the tribes might have some new spells), and a ranger.
The Meeting (Violent):
The Snugladuucians are in their village, farming and beekeeping, when the PCs stroll in. Since the Snugladuuccians have never seen them before, nor recognize their armaments, the fighters meet, with their weapons at the ready (the weapons consist mainly of clubs, spears, and bows. The two groups meet in the village center. Both sides quickly realize that they do not share a language, so the talk consists mainly of sign language. The Snugladuuccians are tense, and ready to fight, because they don't know whether or not the strangers are a threat for them and their families. The PCs, though not wanting to fight, recognize the battle readiness of the Snugladuuccians, and ready themselves for the combat. The PCs, after a few tense minutes of trying to sign 'peace' to the Snugladuucians, draw a sword to draw a picture in the dirt. The tense Snugladuucians take this to mean that the PCs are attacking, and attack first. The PCs themselves see the attacking Snugladuuccians, and turn the sword from drawing in dirt to bloodshed. Though the PCs have the advantage of high levels and steel, the Snugladuuccians have numbers, and the PCs retreat into the forest, with the Snugladuuccians searching the woods behind them, but giving up after they couldn't find the PCs.
The Meeting (Peaceful):
The PCs are walking along one day and see a new tribe (the Snugladuuccians). They then hold a conference amongst themselves on how they want to deal with them, and the general consensus was peace. The PCs then, after noticing a lack of wizards among the Snugladuuccians, decided on 3 magical items they have that are the worst. They then approach the Snugladuucians the first day, demonstated one of the items the first day, draw a quick picture that shows them coming again with a new item, and leave with the item on the ground behind them. They do the same thing the second day. On the third, they give the last item, and open communications with he Snugladuucians. Now, instead of the Snugladuuccians being tense and battle ready, prompting the PCs to be tense and battle ready, the Snugladuucians trust the PCs to some degree. If the PCs were to draw a sword for a peaceful purpose, the Snugladuucians might become wary, but that is it.