The first step in determining whether a cultural property is eligible for listing in the National Register of Historic Places is to consider its context. For the purposes of eligibility, a “context” is a body of knowledge defined by a specific theme or topic, a specific geographic area, and a specific time period. All contexts and context studies are resource-based—that is, they must relate to identifiable cultural resources. Contexts provide the framework for evaluating the National Register eligibility of cultural properties. Idaho has developed several National Register of Historic Places Multiple Property Documentation Forms (MPDs) and historic contexts to guide this work.

Before the term Multiple Property Submission (MPS) was introduced in 1984, such listings were known as Thematic Resources (TR), or Multiple Resource Areas (MRA).