Kano. He is probably the Earthrealm character who has the most varied and well-traveled background. To start with, his mother was American and she orphaned him in Japan. The MK novel states he was actually born in Japan and the name "Kano" is a popular Japanese name. This could mean that one (or both) of his parents was of Japanese descent, and that might help to explain why his American mother was in Japan when she abandoned him.
Despite his genealogy and his having been raised in Japan, Kano has an Australian accent, strangely enough. Now how did that happen?
The MK novel says Kano was 5 years old when the Black Dragon discovered him. He was survived by stealing from American soldiers and natives alike and it so happened that one day he stole from a member of the Black Dragon, who admired his skills and took him in. Scientifically, we know that a child's accent is heavily influenced by the speech they hear when they are about 5 to 7 years old. So it stands to reason that, since Kano's parents were out of the picture, the member of the Black Dragon who took him in spoke with a heavy Australian accent which Kano adopted.
Aside from being of American descent, originating from Japan, and having an Australian accent, Kano has traveled to, and subsequently became wanted in, thirty-five countries. The novel says that in addition to this, he has also been deported from both Japan and America. He was most likely deported from Japan on the grounds that his parents were not legal residents of Japan (although it is possible his father was, but he had no part in Kano's life). Similarly, Kano was not born in the United States so if he were, say, suspected of engaging in illegal activity but could not be convicted of any wrongdoing, he would have faced deportation.