Why were all famous classical composers white?

Because it's just the way it happened. It isn't a racist thing.

I think that you have to have a background in classical music to write it. Black people would not have had such an education, neither would the lower class white people.

Agree with 'Buddha', and would add that many Classical composers lived in countries with a very small Black population - e.g. Tchaikovski, Prokofiev, Mozart, Bach, etc etc all lived in Central or Eastern Europe with next to no Black people. It's not racist, it's just history and geography.

This is pretty simple really. Most of the music was created in times where inhabitants of European colonies resided in their country of origin. There was only very limited migration of inhabitants of the colonies back to Europe. So while all this music creation was going on, there were (for all intents and purposes) no black people living in places like Vienna, Paris, London and the other great seats of culture. So, concluding, I would say (rhetorically) - why would they be anything but white.

That's the history of classical music and nobody can change it may be in the future it might change

I don't know why everyone feels the need to write novels for an answer. This is all that you need to know. The real name for "classical" music is Western European Art Music. It is the indigenous music of Western Europe. At the height of classical music, blacks were either completely unaware that classical existed (thanks to being thousands of miles away from where it was performed) or if they were living in Europe/America, they had no rights. It's not really much more complex than that. It's all just a question of heritage. People write the music of their forefathers. Only now that communication takes place on a worldwide scale are we starting to see people indigenous to one culture writing music of another culture.

Actually, there were many great African American composers of 'that time' (I take it you mean when America was founded and slaves were labored)... Do you sing hymns at church and such? Many hymns were formed in slave churches in America and have been passed on from generations. Think of "Swing Low, Sweet Chariot" an African-American hymn. Moreover, have you never heard of Scott Joplin? One of the greatest [American] composers? He formed America's sound of jazz and ragtime! You can NEVER say "all" there are always some people who were/were not. In this case, not ALL composers were white, there were and still are great African-American composers! Although they do not get as much publicity. Their voices will be heard on in our hymns and jazz.

Geeklchic covers this question very well. I would just add that what we call 'classical' music originated in Europe at a times when any face other than white was a rarity, but China, Japan and India have their own versions of classical music which is ancient in origin. It is not only very important in its own right but has profoundly influenced western composers from Claude Debussy and Gustav Holst to Philip Glass and Steve Reich.

because culturally classical music is german, there were some fantastic black musicians all through out history just not in the classical style. Black people tended to play boogie woogie, ragtime, blues and later on jazz and funk which led on to Rn'B and all the styles we have today!