What is the origin of the idiom "in living memory" and when to use it?

The idiom "in living memory" has its origins in the idea that it refers to events, experiences, or knowledge that are within the recollection of people who are still alive. It is used to describe events or situations that have occurred during a period that can be personally remembered by individuals rather than being so distant in the past that it exists only in historical records. It is most employed in discussions, storytelling, and historical accounts to contrast recent events with those that occurred in the distant past.