The cultures in the world of Pillars of Eternity are in a variety of different technological states. Though some remote civilizations are still in the equivalent of Earth's Stone Age or Bronze Age, most large civilizations are the equivalent of Earth's high or late Middle Ages. The most aggressive and powerful civilizations are in the early stages of what would be our early modern period, technologically, even if they are not culturally undergoing "Renaissance"-style changes.
For most large civilizations, this means that all of the core arms and armor of medieval warfare have reached a high level of development: full suits of articulated plate armor, a variety of military swords, war hammers, polearms(e.g. spears), War bows, crossbows, and advanced siege weaponry. Architecturally, these cultures also employ technologies found in Earth's Gothic structures, allowing them to create towering vertical structures. Notably absent is the printing press, it means that knowledge is not as easily disseminated among the populace. Books are handmade in scriptoriums and similar locations and they aren't cheap.
The most recent technologies seeing use in the world are ocean-going carrack-style ships and black powder firearms. Cultures with large navies and mercantile traffic are exploring the world, which has led to contact with previously-unknown lands and societies and settlement in new lands. Despite their intense drive, these explorers have been restricted from aggressive long-range exploration by monstrous sea creatures that pose a lethal, seemingly insurmountable threat to even the stoutest, most well-armed ships.
Black powder firearms are of the single-shot wheellock variety. Largely considered complex curiosities, these weapons are not employed extensively by military forces. Their long reload times are considered a liability in battles against foes that are too monstrous to drop with a single volley, foes that fly or move at high speed, and foes that have the power of invisibility. Despite this, some individuals do employ firearms for one specific purpose: close range penetration of the Arcane Veil, a standard magical defense employed by wizards. The arcane veil is powerful, but it does not react well to the high-velocity projectiles generated by arquebuses and handguns. As a result, more wizards who previously relied on the veil and similar abjurations have turned to traditional armor for additional defense.
Pillars of Eternity's world is one with limited medicine and medical understanding. Remedies for health problems often have only a palliative or placebo effect at best, owing their continued use more to folk beliefs and tradition than any basis in scientific methodology. Though soul-based magic has helped the great exploring cultures from suffering massive pandemics and has helped some individuals overcome illness over the long-term, there is no quick magical "cure" for disease or illness. Most people go through life and death in the ordinary way—unless they put themselves in harm's way, that is.
The time in which the story of Pillars of Eternity takes place is during an age of discovery for the Eastern reach. Animancy is a young and rapidly-developing field. With the development of animancy comes technology that can significantly change the lives (and deaths) of people in the world — not just kings and knights, but all sorts of people.