Microsoft intended to make the operating system feel instantly familiar and personalized to a user’s home country right out of the box. A user in Tokyo might not feel a personal connection to a wallpaper of the British countryside, while a user in London might prefer images of the UK over the Australian outback.
There’s no official reason, but it created a fun "Easter egg" for users to discover. It also kept the main Personalization menu tidy, showing only the most relevant theme for the user's locale. windows 7 regional themes
Under "My Themes" or "Aero Themes," you can see the currently active theme. Microsoft intended to make the operating system feel