Not a "white name"?

So I'm a little upset, the name we've chosen has been classified as a "black" name, by a group (15+ African American friends at our 4th of July party) of what I consider my friends.

We are what I classify as neon white. As in glow in the dark, can't tan, and the base for my make up is called *translucent*.

They said the name I am picking is offensive to their culture....

The name we have picked out is Octavia.

Is it a black name?

Are we insulting the black culture?

Should we use it anyways?

I really don't want to be offensive but the name dates back pre- Ceasar so I didn't think a culture had a claim to it...

Can anyone give me any insight?