Because the influence of wealthy families who wanted to give their sons a broad education:

many independent artists who did not have ties to the church were drawn to Italy.

Explanation:

The Medieval period or middle ages in Western Europe was characterized by a period of Enlightenment and Reformations. During this period, Western Christianity originating in churches within and around Italy served as the citadel of learning.

Consequently, many wealthy families sought to give their sons a robust education. And because of the rewards to be derived from these wealthy families, "many independent artists who did not have ties to the church were drawn to Italy."

d. promised it other land