How about a subscription to a history movie streaming service like The Criterion Channel or History Vault? Alternatively, you could also get her a DVD or Blu-ray box set of her favorite historical movies, like "Gone with the Wind","Lawrence of Arabia" or "The Bridge on the River Kwai". Another option could be to book a historical tour or visit a historical site or museum, depending on what's available in your area.
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.