Final answer:
European countries began to explore in the 1400s primarily to find new trade routes to Asia and spread Christianity.
Step-by-step explanation:
One of the primary reasons European countries began to explore in the 1400s was to find new trade routes to Asia. The existing land routes along the Silk Road were controlled by Muslim middlemen who imposed high taxes, fees, and transport costs. By exploring new sea routes, Europeans aimed to bypass these intermediaries and establish direct access to valuable goods like spices, silk, and porcelain. Another motive for exploration was to justify and spread Christianity. Catholic nations like Spain and Portugal sought to convert non-Christians and retake territories from Muslims. These two reasons, trade and religion, were key driving forces behind the European exploration during this period.