A more thorough explanation:

Definition: Visitation books are historical records compiled by heralds during royal progresses throughout the kingdom. The purpose of these books was to inquire into the state of families and to register marriages and descents that were verified upon oath.

Example: During the reign of Queen Elizabeth I, heralds were sent out on royal progresses to visit different parts of the kingdom. They would visit noble families and record their genealogy, including marriages and descents. These records were then compiled into visitation books.

Explanation: The example illustrates how visitation books were created during royal progresses. The heralds would visit families and record their genealogy, which was then verified upon oath and compiled into a visitation book. These books provide valuable historical information about noble families and their lineage.