What is the origin of the idiom "have the run of something" and when to use it?

The origin of the idiom "have the run of something" is rooted in the concept of free movement and access. The word "run" in this context refers to the act of moving freely or having the opportunity to roam without restrictions. The phrase likely emerged from the world of hunting, where hunters would release their dogs to chase and pursue game across a designated area. The dogs would have the "run" of the hunting grounds, allowing them to freely explore and track their prey. It is commonly used when discussing situations where individuals are granted the liberty to explore and access different areas as they please.