One idea could be to give her a historical costume or accessory that she can wear when she attends reenactments. You could research the specific time period or event that she enjoys the most and find a piece that is historically accurate.
Another idea could be to plan a weekend trip to a historical site or reenactment event. This would allow her to fully immerse herself in her hobby and experience it firsthand. You could also look into experiences like a historical cooking class or a guided tour of a historical location.
If your girlfriend enjoys reading, you could also give her a historical fiction book set during a time period that she is interested in. This would allow her to learn more about history while also enjoying a good story.
Or you can get her a star map with an important date you share.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.