My 4GGfather was Martin Harris, the man who financed the first printing of The Book of Mormon, and one of the Three Witnesses to said book.
I learned, several months ago, that my Gr, Gr Uncle was appointed to the Oregon Supreme Court in the 1870’s. He ran for the office when his term expired, but was defeated.
All the other men in my line have been farmers and carpenters w/ a couple of school teachers thrown in, so my uncle’s study of the law was unique.
He died in a very small town, in eastern Oregon, in the 1880’s. I plan to go over there, probably in the spring, to see if I can find his grave, and/or any other records of him.
My former wife was directly related to a fellow named Tresham. He was a co-conspirator in the Guy Hawkes affair and, in fact, the one who’s loose talk exposed the plot, causing it to be stopped.
I am related to John Ericsson, who designed the USS Monitor, the first ironclad warship in the US Navy. I am also descended from the Cunard family, who owned White Star Line, who owned the Titanic. Seems we like boats.
One one side (as I posted in the slavery thread) I descend from Virginia tobacco planters, who had to flee from the advancing Union Army.
On the other side, my great(something)-grandfather was a member of the famous Fighting 69th Irish Brigade. When their color bearers were shot down during Antietam, my ancestor was one of the men who put his gun down to carry the flag instead. He was the second-to-last to carry it and took 4 bullets before falling. The guy picked it up from him (his name escapes me) wrapped it around his body and ran up and down the line with it. My ancestor amazingly survived, though he lost one of his legs. He recovered at Point Lookout Military hospital (IIRC), where met President Lincoln.
My family had heard some of this story and we all sort of assumed it was mostly a yarn (I mean, come on, a poor irish kid meeting Lincoln?). But my mom got records from pension application, and in it were all these letters written by prominent members of that regiment (including the guy who took the flag from him and Thomas Meagher, the commander of the brigade) describing what had happened. And Lincoln did tour the hospital at the time he was there.
My Maternal Grandfather was stationed on Tinian at the end of WWII and helped dig the pits they used to load the Enola Gay.
Don’t know if this is far enough in the past to be historical, but my Uncle was in one of the first fire trucks to arrive at the World Trade Center on 9/11, and was part of the search & rescue teams immediately after.
My mother’s mother’s parents were a Korean man and a Bohemian woman in Chicago in the early years of the 20th century. I don’t think that happened all that often.
My mother’s father changed names several times as his mother fled a series of abusive relationships. Then the Depression hit, and they converted to Catholicism because the local cathedral had the best food baskets.
One of my great, great (not sure how many greats go in here) grandfathers was this guy.
Slee
My great-great-grandfather was a Confederate soldier, and bravely took part in the surrender at Pensacola. (OK, not technically a surrender, but similar in effect.)
My aunt was the first female CPA in the state of Washington!
I ain’t got much, but my Dad was one of the cadre of engineers who made the Apolloflights possible. IIRC it was Apollo 8 that he worked on.
That was a dreamy summer, with Daddy away most of the day at Uni; my evenings spent sneakin near enough to the grownups to hear the young engineers discussing the finer details of sending a manned spacecraft to the Moon over a cold beer or three. My Mom would kick them all out at midnight. It put a wonder in me that exists to this day. 
Other than that, my daughter has a male relative who was one of few Choctaw children who lived through the massacres around the time of the Trail of Tears. He was resuced and raised by a white family.
[QUOTE=badbadrubberpiggy]
My grandfather was in the US army during WWII, and was at the liberation of Buchenwald.
My great uncle was also one of the liberators of Buchenwald. He took photographs of the liberation with a camera that he concealed on his body throughout most of his service on the European front.
The founder of my line was the third son of the first king of the Chosun Dynasty. He could have inherited the throne if he had been ambitious enough, but after watching his brothers squabble over the crown, he wisely decided to step back and prosper quietly. For which his descendants are eternally grateful. 
Mrs Geek is really into genealogy and in digging in the last couple of years, she has discovered quite a few interesting things in her family tree. She’s found all kinds of birth and marriage records that don’t quite line up as they should. She also found that she’s eligible for both the Daughters of the American Revolution and the Mayflower Society. She shares a common ancestor with George Bush (not that we’re likely to be invited to the White House any time soon). On one of the genealogy boards she frequents, they noted that Dubya’s ancestor fell off the Mayflower at some point and had to be fished out of the water. Someone made a snarky comment that they should have left him with the fishes.
Related to the OP, Mrs Geek found an ancestor who fought at Antietem in the civil war, and was later captured. They became one of the lucky few to survive the horrors of Andersonville.
Supposedly my great great grandfather on my mother’s side moved here with his family from Russia after killing a Cossack cavalryman who tried to loot his house.
On my father’s side, my great great grandfather was a Greek immigrant who sold stuff from a horse-drawn cart. It is a family legend that his horse was green. How this could have been possible, I have no idea. I like to think that he dyed its fur green to try to attract attention, as a clever marketing ploy. (Or maybe he was an early user of LSD.) The name of the horse was Bonzingo.
A cousin of mine wrote a hymn, “Softly and Tenderly,” that was extremely popular in its day, and is still well-known enough that there are dozens of versions on iTunes (including by Elvis Presley, k.d. lang, and Garrison Keillor and the Prairie Home Companion cast).
My great-great-grandfather was mayor of a small Ohio town. His son was county prosecutor but was called “judge” to the end of his days (even though he never served as one) because of his learned, sober and respectable bearing.
My parents lived in Princeton in the 1950s, and my mom sometimes saw Albert Einstein riding his bicycle around town. She also met Eleanor Roosevelt while she was in her early teens. Her dad ran for Congress on the “pro-FDR Democratic” ticket (the NJ Dems were pretty badly splintered at the time), but lost.
I’m 99% sure on Herbert, 75% sure on William, and 50% sure on J. Edgar.
December, 1930. Grampa Doug is in Boone, IA, selling newspaper ads. He has been corresponding for several months with the soon-to-be Gramma Doug, whom he first met at her parents’ home in Des Moines, and they have finally agreed to marry.
Trouble is, she’s teaching school in California, and he’s got to get a ring to her somehow. Ideally by Christmas. He decides on an unimaginable extravagance: air mail. Won’t that make a statement!
The ring leaves a Des Moines jeweler’s and is put aboard a Western Air Express Fokker trimotor. At Helena, Montana, the plane comes down to refuel in darkness, snags a power line and slams into a house. No one is badly hurt, but the house, the Fokker and most of the mail burn up.
Now Grampa Doug is a tight man with a dollar. On learning of the air mail crash, he is NOT about to let his precious cargo be given up for lost. Diamonds don’t burn, he tells the postal inspector at Des Moines, and by Og you people better find that ring!
Happily, inspectors at the crash site do find the ring, and it proceeds on its way to Huntington Beach, some two weeks late.
The human-interest angle of the frustrated small town newspaperman and the lost ring makes the Associated Press wire and runs all over the country.
Epilogue
April, 1931. All Fokker airliners are grounded after legendary coach Knute Rockne is killed in a crash. The plywood airframes are found to be prone to stress cracking. Federal regulations soon specify all-metal structures for commercial aircraft.
June, 1931. Gramma & Grampa Doug marry at her parents’ home in Des Moines. They are married for 59 years until her death at age 91. Grampa Doug follows 2 years later, a tightwad to the last.
Hey, I had just been searching for info on the Irish in the civil war because of my two g-g-grandfathers who came over from Ireland to fight and I had just found both their names on a roster for the Fighting 69th. I’m not 100% sure it was their regiment because I would think their names would be fairly common but so far that’s the only Irish brigade I could find that had those names on the roster.
My father had worked in the quartermasters office that did whatever quartermasters did with the two A-bombs later dropped on Japan.
My great-x grandparents that I share a last name with arrived in the New World at the 1st colony at Jamestown around 1610. That was unusual because not many married couples came to Jamestown and it was even more unusual that they almost certainly intended to stay here. They soon moved away from the Jamestown Village proper and started a plantation that exists in name to this day (take that Pilgrims).
They adopted an Indian boy as kind of a house servant. His name was Chanco and he still had contact with his tribe. One day, Chanco became very upset and spilled the beans that a massive Indian attack was about to occur. My ancestor rowed several miles warning the plantation owners and villagers.
That attack still occured killing about 1/3 of Jamestown (347 people) but the colony itself survived. American history would likely be quite different if it weren’t for my ancestors and their adopted Indian boy.
My eight-greats grandfather was the first Amish bishop in America.
My great-aunt worked for the CIA.
My grandfather got around a lot. I don’t know if he’s exactly famous, but he knew everybody just about everywhere he went, and they were usually important everybody’s. Like, the mayor, the whole chamber of commerce, that sort of folks. I wish I’d been smart enough to realize what an opportunity he was handing me by dragging me around to meet all these folks before we went fishing, but I was only a young’un and was bored by all the suits. Doh!
I don’t know how to verify (short of calling up an Air Force base and getting laughed at a lot), but family legend has it he worked on the Enola Gay, though not for the mission that made it famous. He didn’t like talking about the war much and tended to brush off questions, so I don’t have many corroborating details.
Also, he worked on a CCC crew in Idaho for a time, and his picture actually still exists to this day on a US Forest Service historical information site at one of the locations that the CCC did a lot of work. I try to visit it at least once a year just to make sure they haven’t taken it down yet.