Funnily enough, one the reviews of the book (by "the Bonneys") that you say you cannot find anywhere, says that Doane doesn't deserve a 622-page book. On the other hand, this review does say:
He did participate in the controversial Marias massacre in 1870, but on
other occasions he does not seem to have been involved in action. This undoubtedly
explains why he was not promoted to captain until 1884, a rank which he
still held when he resigned in 1891.
It's not clear from the review if the book details his participation in that event or not. Anyway, the review is signed off by
Richard N. Ellis
The reviewer, a member of the history faculty at the University of New Mexico, recently published General Pope and U.S. Indian Policy.
So at least the claim appears "fact checked" by historian who has published on such matters.
There are two other reviews of that book that don't mention this fact though. And one of these reviews describes the book as rather hagiographical, so I suspect the book doesn't actually mention this fact either, or it might be buried in all the other "trivia" that that reviewer accused the book of being stuffed with. So, from that, I suspect his participation wasn't broadly known in the 1970s (when that book was written).
On the other hand, the somewhat obscure Platte County Record-Times has this more extensive quote in a 2019 piece
According to a summary of the 1870 Marias Massacre, prepared by staff for the U.S. Board of Geographic Names, Doane’s commanding officer had been told to attack a hostile band of Piegan Blackfeet outside present-day Dunkirk, Montana. However, after an error, Major Eugene Baker directed his troops to attack a different, non-hostile band of Piegan, who’d been promised protection by the federal government.
“Reports of those killed varied, but as many as 217 Piegan, mostly women and children, were slaughtered,” according to the national board’s research. “At the time, most of the young men were away hunting bison; many of the band were also suffering from smallpox.”
Despite being part of an attack on the wrong group of people, First Lt. Doane took pride in what he called “the greatest slaughter of Indians ever made by U.S. troops.” When he later lobbied to become the first superintendent of Yellowstone National Park, Doane cited the massacre as an accomplishment.
“I remember the day when we slaughtered the Piegans, how it occurred to me, as I sat on the bank of the Marias [River] & watched the stream of their blood, which ran down on the frozen river over half a mile, that the work we were doing would be rewarded, as it has been,” Doane wrote in 1891.
Doane didn’t get the park position and died the following year at the age of 51.
It's not precisely clear (from that article) from what writings of Doane the quotes are though.
Finally, there's a more recent (2007) book Yellowstone Denied (by Kim Allen Scott, U. of Oklahoma Press), but which predates the BGN inquiry,
which describes Doane's participation in the massacre in detail on a few pages (pp. 66-68).
This is the most unflattering description, because not only was Doane a
clear participant, but apparently he put the lives of his own troops in danger
from cross-fire from another (US) position. I'll only quote one para from that:
Doane had placed Sergeant Anderson’s men in a very precarious
position on the bluffs opposite the main column, but the only real
danger they faced were the bullets from their own comrades, who
were ‘‘firing in their direction constantly.’’ Even though they risked
death by friendly fire, the men of Anderson’s squad stood their
ground and poured volley after volley into the village. The Piegans
who attempted to flee in that direction were shot down, and several
had to be chased high up on the slope and killed with revolvers.
Some of the Indians managed to escape the hellish fusillade by
hiding in the brush, however; and in spite of the soldiers’ best efforts,
a few survivors escaped to warn other villages downstream. The awful
firing continued until Baker ordered Doane to mount his command
and ride down and continue the carnage at close range. Doane led
his men forward. As they swept through the village to complete the
work he watched his men pause in front of lodges and fire into
doorways to silence the screams of the occupants. Not all of the
soldiers could stomach the slaughter, though. Some of Doane’s men
held their fire to capture hysterical women and children who poured
out of the perforated lodges and herded them together into a bunch.
Furthermore, this book alleges that Doane ordered the execution of some prisoners
Baker left Doane in charge of the village with Company F while he led
the balance of the command in pursuit of Mountain Chief. Doane
completed the destruction by having his men pull down the lodges,
stack dead bodies and foodstuffs on top of the collapsed tepees, and
set fire to them. The work of destruction continued all day; and as
night fell Doane posted a guard around the 140 women and children
who had escaped immediate death. ‘‘Sergeant O’Kelly was on guard
that night and is entitled to great credit for his energy and alertness,’’
Doane would recall years later, ‘‘the camp being full of wounded, the
sentinels firing at intervals all through the night, which was made
hideous by the groans of the wounded, the howling of the dogs, fire
breaking out in the woods, and the stampeding of the pony herd in a
tremendous wind storm.’’ According to hearsay evidence, even
darker events may have occurred that night. Pvt. Daniel Starr recalled
to a comrade years after the event that eight warriors had been
captured with the women and children, and during the night two
made a desperate bolt for freedom into the freezing darkness. Starr
claimed that after troopers recaptured the warriors, Doane lost his
temper and ordered all eight of the men executed. When the troopers
prepared their carbines, Doane said, ‘‘No, don’t use your guns.
Get axes and kill them one at a time.’’ Starr admitted that he and the
other guards quietly dragged the prisoners out from the tepees they
shared with the women and children and obediently performed the
gruesome duty.
These paras are amply footnoted with the sources used, mainly:
- Gustavus Doane, ‘‘Lieutenant Doane’s Report,’’ in Rodenbough, From Everglade to Canon with the Second Dragoons, 552–53.
Starr's accusation comes with this footnote:
Starr’s accusation was recalled in the 1920s by William White, who out of respect for Doane may have intentionally garbled the particulars. White said that Starr only identified the man giving the order to execute the prisoners as the ‘‘officer of the guard’’ and that the murders took place during the return march of the soldiers to Fort Shaw. None of the prisoners accompanied Baker’s command on the return march, however, so the only evening the alleged incident could have taken place was the night of January 23, when Doane was the sole officer left in the
captured Piegan village. White, Custer, Cavalry & Crows, 33.
Towards the end of this book, in the final chapter on his bid for Yellowstone superintendency, is noted (p. 251) the context of his bragging (that was highlighted in the BGN thing)... and in fact there was more than one such occasion in Duane's correspondence:
Once
again he felt he had been arbitrarily passed over for the Yellowstone
detail and reacted with a rage that overwhelmed any sense of precaution.
In a letter to Senator Wilbur F. Sanders of Montana, Doane
used a particularly insensitive argument, considering the recent
events at Wounded Knee. ‘‘I want command of the Yellowstone National
Park,’’ he railed. ‘‘If I have not deserved it justice is a mockery,
merit a scandal, gratitude a farce and liberty a lie. I remember the
day when we slaughtered the Piegans, how it occurred to me, as I sat
down on the bank of the Marias and watched the stream of their
blood, which ran down the surface of the frozen river over half a
mile, that the work we were then doing would be rewarded as it
has been.’’
When it became obvious that Senator Sanders would be of little
help in the matter in Washington, Doane wrote with even more force
to James K. Clark of the Montana House of Representatives in
Helena. In a letter similar to those he sent to every member of the
legislature that he knew, Doane demanded their assistance by again
insisting his participation in the 1870 massacre of the Piegan camp
entitled him to Montana’s support. ‘‘If the Montana Legislature will
pass on a joint resolution, asking of the President my detail, it will
throw a bombshell into the federal camp,’’ Doane wrote, ‘‘which will
open the eyes of some of those staid old Eastern Christians, who
prefer a howling savage to a Western farmer, and an effeminate dude
to a pioneer.’’ The joint resolution never passed, although nearly
every member of the Montana legislature did sign a petition on
March 3, 1891, asking that the federal government appoint Doane
superintendent of Yellowstone.
And on an earlier/unrelated occasion (p. 70)
When asked by ‘‘an anxious settler’’ quoted
in the Deer Lodge New Northwest if he thought the Montana tribes
would remain peaceful as a result of the massacre, Doane replied,
‘‘Well, I can’t say, but there are certainly 173 very good arguments in
favor of their remaining quiet, laying out on the Marias!’’
It's also noted in this book's epilogue that despite the fact that historian Merrill Burlingame had acquired most of Doane's papers, he was "scooped" in the publication of a biography by the amateur Texas couple ("the Bonneys") whose book is hard to find nowadays, so no book-length academic biography of Doane was published until the 21st century, essentially. Burlingame only donated his Doane collection to Montana State University Libraries in 1992, a couple of years before his death.