What law prohibited marrying between racial groups and ultimately led to pacific islanders marrying into tribal communities?

I believe the answer is: anti-miscegenation laws (also known as miscegenation laws)

The law was created in 1871, with the purpose of preventing the freed slaves and other minorities from obtaining power within the society.  The law lasted for almost a century, until it was ruled as unconstitutional by the united states supreme court in the year of 1967.

c. had saved colonel cresap's family from attack by other native americans.