Who were theProspective voters had to read and explain difficult parts of the Constitution.

A literacy test assesses a person's literacy skills: their ability to read and write. Literacy tests have been administered by various governments to immigrants. In the United States, between the 1850s[1] and 1960s, literacy tests were administered to prospective voters, and this had the effect of disenfranchising African Americans and others. Other countries, notably Australia, as part of its White Australia policy, and South Africa adopted literacy tests either to exclude certain racialized groups from voting or from immigrating.

Explanation:

a historian researching the immigration policies of the early 1900s would expect a source written today,rather than in 1910 to :

( a ) be more interested in objective data and statistics.

the western roman empire flourished, but the eastern portion of the empire struggled.