Final answer:
A person who traveled to new lands to convert people to Christianity is called a missionary, playing a key role in the Age of Exploration and colonialism.
Step-by-step explanation:
The term that describes a person who traveled to new lands with the goal of converting people to Christianity is a missionary. These individuals, both clergy and laypersons, played a significant role during periods of exploration and imperialism as they established churches and schools to spread Christianity and the language of the colonizing nation.
Missionaries often received support from the rulers of the new territories, with their conversion sometimes critical to the broader spread of the religion. Over time, this missionary practice became part of the larger efforts of European countries during the Age of Exploration and colonial expansion to proliferate Christian beliefs and to integrate indigenous populations into the societies of Christian nations.