The actor makes his feelings known in an interview with The Sunday Times, telling the UK publication ... "Black History Month is an insult. You're going to relegate my history to a month?"

Morgan feels the same way about "African American," explaining ... "I don't subscribe to that title. Black people have had different titles all the way back to the n-word and I do not know how these things get such a grip, but everyone uses 'African American.' What does it really mean? Most Black people in this part of the world are mongrels. And you say Africa as if it's a country when it's a continent, like Europe."

Morgan made the comments in response to a question about an old TV interview he gave way back in 2005 ... when he said the only way to end racism is to stop talking about race.

In the old interview, Morgan tells the TV host ... "I'm going to stop calling you a white man and I'm going to ask you to stop calling me a black man."

The Sunday Times asked if he still feels the same way, 18 years later, and that's when he went off about Black History Month and using "African American" ... reportedly raising his voice as he explained his view.

When the interviewer quoted Denzel Washington as once saying, "I'm very proud to be Black, but Black is not all I am," Morgan says ... "Yes, exactly. I'm in total agreement. You can't define me that way."