She was the Rosa Parks of her day. One hundred twenty-nine years ago, Black educator and activist Ellen Garrison Jackson Clark was buried in an unmarked grave in Altadena's Mountain View Cemetery and forgotten.

Recently, the mystery of Clark's final resting place was solved. In an interview for "LA Times Today," staff writer Jeanette Marantos joined host Lisa McRee with the story.

Clark's celebration of life was held on Juneteenth, the holiday commemorating June 19, 1865, when word of the Emancipation Proclamation belatedly reached Texas. The ceremony brought together a diverse, standing-room-only crowd in the cemetery's Sunrise Chapel. In Massachusetts, members of the Robbins House Museum watched the ceremony live online.

Marantos says she found this story in her local newspaper, in the sections that mentioned Juneteenth activities. After delving into the story, she realized most of what is known about Ellen Garrison Jackson Clark is from her letters.

"The letters reveal that she has great handwriting and that she was a brilliant and fearless woman. She spent about 40 years teaching three people in the South how to read and write. And she endured a lot of harassment from the white community where she was. She has one quote: 'It is only occasionally that I have been beaten and stoned in the street.' She has another where she was applying to the American Missionary Association, saying: 'I think it is our duty to spend our lives and try to elevate our race.' That was her opening sentence when she was applying for this job."

Ellen Garrison Jackson Clark managed to get her passport in 1850 even though slavery was not outlawed until 1865.

"She had a little scrap of paper and whatever information she could get from the American Missionary Association and the Freedmen's Bureau, which was working after reconstruction to help people who had been freed and had nothing, clothing, housing, anything. But the biggest thing we learned, one of the biggest things we learned is that she was one of the first people to contest the Civil Rights Act of 1866, which didn't have a lot of penalties associated with it. But it was the first thing that Congress passed saying that African-American people have rights as citizens of the United States. And she got thrown out of the lady's waiting room in a train depot in Baltimore. She said she was thrown, literally thrown out from sitting in the lady's waiting area as she was so indignant, and she filed suit under that law," Marantos said.

Much of the information that is known about Ellen Garrison Jackson Clark was pieced together by the Robbins Museum in Concord. And, she also spent her final years of life in California.

"All we know is that she died here in 1892 from consumption, which is what they called tuberculosis in those days. And she was buried in an unmarked grave in the northwest corner of Mountain View Cemetery in Altadena. Given that she spent almost 50 years teaching and working for civil rights, we can speculate that she may have been active once she came to California. But we know she was here less than two years with her second husband, Harvey Clark. And we don't know if she was well enough to do much of anything, but it would have been out of character for her if she had been well enough. It would have been out of character for her not to be involved in some way," added Marantos.

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