The 1880 U.S. Census recorded a John Oberlander living in Fon du Lac, Wisconsin. His wife is listed as Isabella Oberlander, a white female, age 30.
Isabella’s maiden name was Jones, and in the 1870 census she was recorded as a mulatto female, age 20.
Isabella was my great-great-grandmother. My family did not know about these census records until less than 10 years ago, and we were not certain to what extent they were reliable. But a few years ago I had my genes sequenced at 23andme.com, and it showed I had 1.7% Sub-Saharan African ancestry. That would correspond to my being about 1/64 black, and Isabella being about 1/4 black — which is presumably what enabled her to pass as white.
Through much of the 20th Century, some states classified people as black or white using the “one-drop rule“: if you had any black ancestry, you were considered black. The Supreme Court finally struck down those racial classification laws in Loving v. Virginia, the case that legalized interracial marriage nationwide. That case was decided on June 12, 1967 — about three months after I was born. So, for a brief part of my life, in some states, I would have been legally classified as black.
At the time I was born, the Church of Jesus Christ of Latter-day Saints, of which I am a member, did not allow anyone with any black ancestry to be ordained to the priesthood. Fortunately, that was changed by Official Declaration 2, on September 30, 1978 — about six months before I was old enough to be ordained a deacon.
Of course, since my great-great-grandmother Isabella passed as white and did not let her descendants know of her black ancestry, no one would have known I was legally black in some states or that I could not be ordained to the priesthood in the LDS Church. It wasn’t until my DNA test in 2013 that I knew for sure. However, that knowledge has certainly made the issues of slavery, racial segregation, and the priesthood ban for blacks feel a lot more personal to me.
Legally, the question of how much black ancestry is required for someone to claim to be black appears to be open. The U.S. Census Bureau allows you to self-identify your race.
However, because I look white and was brought up as white, I don’t feel like I really have any right to identify myself as black on the basis of 1/64 ancestry. So you probably won’t see me on any lists of black science fiction authors. (It’s different when it comes to identifying as Hispanic, because I did spend a significant portion of my childhood in Latin America, I was brought up bilingual in Spanish and English, and I knew my father was born and raised in Argentina.)