Final answer:
Because of the reformation and Protestant iconoclasm, many Northern Renaissance painters shifted from religious artwork to secular subjects like history painting, landscapes, portraiture, and still life. They also reflected Protestant values through clear and accurate depiction of people and stories, as exemplified by the works of Bruegel.
Step-by-step explanation:
During the period of the Protestant Reformation, there was a significant wave of iconoclasm, leading to the destruction of religious imagery, as many Protestants perceived religious art as a form of idolatry. Artists in Protestant countries thus began to shift their focus from religious subjects to a more diverse range of secular subjects. This change included history painting, landscapes, portraiture, and still-life. Furthermore, artists began to infuse their work with Protestant values which emphasized a more personal and direct relationship with God, portraying people and stories more accurately and clearly without the embellishment common in earlier religious artworks.
One key artist of this period, Bruegel, contributed significantly to the development of Western art, as his work reflected the societal changes and responded to the Reformation's call for artwork that shunned the Catholic Church's lavishness and focused on simplicity and didacticism. As a direct response to iconoclasm and the Protestant call for clarity, painters used their talents to depict scenes that conveyed a moral message, often using detailed narrative scenes from the Bible or everyday life to engage the viewer.