'historical' as an adjective refers to something related to history or past events.
'Historical' is used to describe something that belongs to the past, not the present. It can be used to describe events, periods, places, artifacts, and more. It's important not to confuse 'historical' with 'historic.' While both are adjectives, 'historical' refers to anything related to the past or history in general, whereas 'historic' refers to something significant or important in history.
The historical documents were kept in a special archive to preserve them.
She is researching the historical context of the Victorian era to understand its literature better.
The museum displays historical artifacts from ancient civilizations.
Be careful with the distinction between 'historical' and 'historic.' A building might be described as 'historic' if it played a significant role in some event, but 'historical' if it's simply old and from a particular period in the past. Sometimes 'historical' is used in the context of research to indicate that one is looking at how something has changed or developed over time.