One important advantage that primary soruces have over secondary sources is that primary sources offer a firsthand account of an event - b, which isn't the case with secondary sources. Although this leaves primary sources prone to being biased compared to secondary sources.
The supporters you're referring to were called patrons. Patrons were usually wealthy merchants or people who have made their fortune in other ways and wanted to either have a picture of themselves and their family, or generally had a desire to support painting, some even decided to order paintings for the church in order to get in good standing with the church officials.
Answer:
Nativism: protecting those who are already inhabiting and existing in an area against newcomers or immagrants
Examples:
Chinese Exclusion Act
Immigration Resctriction League
Most people gained disease
