Mrs. Lee, General Robert E. Lee's mother who lived in Stratford, Virginia, had been in poor health so long that a doctor was in almost constant attendance. She suffered from catalepsy, a trance-like affliction. During a long trance when she was pronounced dead, the lady was prepared for burial and on the third day, after the funeral, was placed in the family vault at the cemetery. The sexton, while cleaning up and placing some flowers on the casket, heard a faint noise. He listened intently and detected a faint call for help. He opened the casket and found Mrs. Lee Alive!
Mrs. Lee slowly regained her health. Her son, born for fame, came into this world more than a year and a half after she was placed in her tomb.
At least some of the emigrants who died en route to Oregon were probably buried alive because the survivors were in a hurry.
For many years, cholera ravaged emigrants along the Oregon Trail. Whoever caught it was dead--no cure or treatment existed. Usually, the infected emigrant died in 24 hours or less, so if an entire wagon train stopped for an elaborate funeral, it would slow their progress. It was urgent they travel quickly. Too many delays meant the pioneers might not get to Oregon before winter--and then everyone might perish.
So on most wagon trains, the burials got shorter and shorter as more and more people died. Some even abandoned the terminally sick by the side of the Trail, where they would eventually die alone. The more humane wagon companies elected a "watcher" to wait with the dying person while the wagons forged ahead. It wouldn't take long for the watcher to catch up; a quick death, after all, was imminent.