Final answer:
Spanish explorers introduced systems of overwork and servitude and brought about diseases like smallpox, while French explorers entered into trade alliances but also caused territorial conflicts, leading to profound changes in the lives and societies of Native Americans.
Step-by-step explanation:
European exploration, particularly by Spanish and French explorers, profoundly impacted North America. The Spanish colonization efforts brought about the encomienda system, which forced many Native Americans into servitude and altered their societies dramatically. Additionally, the Europeans introduced diseases such as smallpox to which the Indigenous peoples had no immunity, causing widespread death and decimating populations. The French, on the other hand, often formed trade alliances with Native American tribes, and yet their presence led to territorial conflicts while still contributing to the cultural and economic alteration of Native American ways of life.