The word historical in English is usually associated with something that has to do with history or the past. This word is used when we talk about events, objects or people that are somehow related to history, but are not always so important to be included in books about the most famous events.
For example, historical events are any events that happened in the past and left a mark on history. But these won't necessarily be the most high-profile events, such as wars or revolutions. They can be small events that are still important for understanding how history has unfolded.
When we talk about historical documents, we mean letters, books, records, or other materials that have survived from past times and help us learn about how people lived in the past, what they thought, and how they made decisions.
Also, the word historical is often used when we talk about buildings, places or objects that have been around for a long time, for example, historical landmarks are places that have historical value because they are connected to important events or personalities in the past.
Thus, historical is used for anything that relates to history, but does not necessarily make something outstanding or unique in a historical context.