WordPress Permalink Manager Plugin

Make sure all TARGET Media is attached to a Page (not a Timeline Event)

   Wordpress calculates the Default URI / Original URL* as WhatEverItIsAttachedTo(IfItIsAttached)/NativeSlug (It is not saved, instead calculated)

   The NativeSlug is stored in the wp_posts.post_name Table.Column, and can be easily modified with a SQL query

"Tag" the desired media to change with a custom date (1999-09-13, AKA September 13, 1999) using the Bulk Edit feature of Admin Columns

Use a SQL Query to add / prepend the new custom path (example: recent-history/images/, no leading /, but add the trailing)

Permalink Manager, Tools, Regenerate / Reset, Mode: Use Original (Default) URLs as custom permalinks

Optional (Not recommended as it can be done via SQL): Permalink Manager, Tools, Regenerate / Reset, Mode: Regenerate Native Slug

*NOTE: Permalink Manager exchanges the use of "Current URI" with "Custom Permalink" in the Regenerate/Reset Tool

   ...and "Default URI" with "Original URLs" too.

Permalinks Manager: Regenerate custom permalinks and Use original URLs as custom permalinks does the same thing

(The Default URI is copied to the Current / Custom URI)

recent-history11/attachment11/salton-sea-stuck-boat-high-res-no-rv-not-as-vivid11

recent-history/attachment/salton-sea-stuck-boat-high-res-no-rv-not-as-vivid22

recent-history11/attachment11/salton-sea-stuck-boat-high-res-no-rv-not-as-vivid11

recent-history/attachment/salton-sea-stuck-boat-high-res-no-rv-not-as-vivid22