Though it was previously well-known that Michelle's roots on her father's side led to slavery, less was known about her mother's lineage.
However, an article in The New York Times Thursday, "In First Lady's Roots, a Complex Path From Slavery" traces Michelle's family tree back to the plantations on her mother's side, as well.
On "The Early Show", Megan Smolenyak, the genealogist who compiled the research for the report, shared some of the lesser-known details of Obama's family lines.
Smolenyak said she was drawn to one person in Obama's family tree: her great-great-great grandmother, Melvinia, a slave who was documented to be worth $475 in one plantation owner's will.
"She was just fascinating," Smolenyak said. " ... I found where she's first mentioned. ... She's only six years old, and in that document, her first owner, David Patterson, is leaving her to his wife when he passes away."
Smolenyak followed Melvinia's life. She found that, when Melvinia's owner died two years after the will was written, she was shipped against her will to a smaller Georgia plantation owned by the Shields family, which Patterson's daughter had married into.
Smolenyak said Melvinia had four children while with the Shields family. In a census document, some of the children were listed as "mulatto" or of mixed race, Smolenyak said. This could indicate, Smolenyak said, one of the white members of the Shields family was the father of Melvinia's children, meaning Melvinia and an unknown white man are the great-great-great grandparents of Michelle Obama.
"The first good guess would be somebody from the Shields family, but we don't know that," Smolenyak said.
Another of Michelle's forebears became a property and business owner in Birmingham by 1900 -- Melvinia's son, Dalphus T. Shields.
"(He) opened his own carpentry shop, owned his own home by 1900, which back then, put in context, very few people owned their own homes," Smolenyak said.
"Early Show" co-anchor Harry Smith pointed out that, on the day Dalphus died, in the early 1950s, his funeral notice was listed on the front page of the black Birmingham newspaper on the same day the Jim Crow laws were outlawed by the Supreme Court.
"(It's) astonishing," Smolenyak said. "He was born into slavery, he lives long enough to see the baby steps of desegregation, and a descendant of his would wind up in the White House."
Dalphus was Michelle's great-great grandfather.
As for researching your own history, and particularly for African-Americans, Smolenyak said you have to be prepared for what you find.
"It's different to different people," she said. "It is jarring if your ancestors show up as a piece of property, so that's something you have to prepare yourself for, but most people just want to find the truth."