Building a new world from scratch can feel like a monumental task.
So a world's history might be left until needed, or made up on the fly as required.
Investing time and creative effort into events, places and NPCs your players may never see can seem like a waste.
But even if the PCs never see those historical foundations directly, the world will feel more coherent,
interconnected and believable.
1.
Power and politics are the movers of events big and small. Giving thought to the history between neighboring territories creates plot opportunities and fleshes out the types of encounters your party might expect when traveling.
Consider historical alliances and rivalries - look for border locations which may have changed hands or be disputed.
Historic events can be the bedrock of friendship or the seeds for embedded cultural mistrust.
If you are going to have different cultural groups, think about how they have interacted over time and what the main historical features of those interactions might be.
It is worth having some notes on the most recent history between such power blocs too as a backdrop to your game.
2. Artifacts. There are no archaeologists more determined or steadfast than a party in search of some lost artifact or treasure.
Their practice in the field may leave much to be desired (for the pure archaeologist) but they will delve deep into archives, wade through bog and hack through jungle if properly motivated!
The more rounded your historical context is for this type of quest, the richer will be the experience.
A dungeon setting need only be part of a wider journey of discovery encompassing encounters, rival groups, puzzles and historical texts (possibly encoded).
3. Timeslip. Having a rich history allows the GM to send players back through time to experience some of it.
This can make a nice change of setting without the need for much in the way of new resources (geography doesn't change but many settings will be unfamiliar - or not built yet!).
You can bring your history alive by letting your players experience it. This will add to their understanding of your world when they are returned to the present era.
A final thought:
Much can rest on a small point of history. The fortunes of many families have been made and broken upon the slightest point of historical record.
Property, title, influence, legitimacy; all may be found in history.
Happy Gaming!
Stolph