Another confusing pair of words. It's very easy to mix them up because these adjectives are very similar to each other.
When we say 'historic' we mean that something that we are speaking about is important in history. While 'historical' refers to something that simply describes the past.
Compare these examples 👇
It was a historic moment when the Soviet soldiers defeated Nazi Germany = this moment has played an important role in the world history.
Her historical researches are outstanding = researches that are connected with history, they describe the past.
More examples 👇
Kennebec Historical Society gets $1,500 grant. centralmaine.com
Today's mortgage refinance rates see little change as market clings to historical lows. foxbusiness.com
Historic vaccine race meets harsh reality. politico.com
Ontario names 126-year-old Graber Olive House a historic district. dailybulletin.com