The deer did not live on the prairie. They lived along the river bottoms. You quoted and linked to plenty of supporting evidence of that yourself, including the names of the particular rivers and references to the misfortune of the local ranchers who had no better game handy.
The western boundary of the deer range in MN was the prairie edge, because the western part of the State was mostly prairie and deer don't live on prairies.
There are some river bottoms with woodland, and some deer were found in them in the old days - nothing like now, with human farms and human woodlots instead of prairie and plenty of browse and no competitors or predators.
You don't read your own links, let alone mine.
That's why it wasn't "contrary" info - it agreed perfectly with my observation that deer in Minnesota are mostly parasitic on human landscape modification. As Roosevelt noted in your link, the deer moved in after the ranchers brought in cattle and planted windbreaks and broke the sod for farming and suppressed the wildfires - and killed off everything else, including the predators.
Its YOU who doesnt read the links.
QUOTE from first Two Paragraphs of link I provided:
Little mention was made of the deer of this region by the early explorers, as most of their attention was taken up by the other more abundant and conspicuous forms of game. Alexander Henry rarely mentions them in the Red River country, and their principal use seems to have been to provide skins for clothing. Along the Missouri River bottoms, however, they were so numerous in the timber
and lake regions that their numbers were often commented upon by Lewis and Clark (1893, p. 174, 233, 237) on their expedition up the river in 1804-5. On October 20, 1804, on the great flats just below the present site of Bismarck, great numbers of deer were reported. At Fort Mandan and old Fort Clark, these deer furnished an important part of the winter's food supply of the expedition as it wintered among the Indians. On one trip a hunting party brought in 40 deer, 16 elk, and 3 buffalo. On another trip a few miles down the river, February 21, 1805, Lewis returned with 3,000 pounds of meat, having killed 36 deer, 14 elk, and a wolf.
Many deer were mentioned at other localities along the river on the way to Fort Union (Buford).
In 1833 while wintering among the Mandan Indians, Maximilian (Wied, 1839-1841, Bd. 2, p. 84, 1841) reported the white-tail as found in the nearest woods not a mile from the fort,
while all other game was kept at a much greater distance by the Indians, who were constantly hunting for meat.
The
disappearance of these deer from the
greater part of North Dakota was coincident with the settlement of the country. While they were quickly destroyed, however, or driven from the small areas of cover, the more extensive areas are still preserving them in some decree of abundance locally. At Fort Sisseton, just below the southeastern corner of the State, Doctor McChesney (1878, p. 203), reported them as very common 10 years before, but said that none had been seen in that vicinity for several years. At Valley City Morris J. Kernall was told by several of the early settlers that
white-tailed deer as well as mule deer
were common there from 1878 up to 1885 or 1886, and one was reported by Frank White as killed in 1893. At Ellendale, in the possession if Fred S. Graham, Sheldon found a mounted head of a deer killed in the hills 12 miles northwest of Forbes in 1886.
Additionally, you missed this bit even though it was included in my org. snippet:
In Roosevelt's long and interesting account of the habits and methods of hunting these deer he gives a good picture of their
former abundance and rapid disappearance after other more easily obtained game had vanished, and he pays a well-merited tribute to the cunning and sagacity of the animals in protecting themselves, even where the country became well settled.
Driving around Custer State Park S.Dakota, its obviously much easier to shoot a buffalo than a white tailed deer. I dont blame the settlers a bit for going after the easy shot vs trying to hit a bounding, leaping 40 mph target.
And there is a bunch more if you would just flipping READ the Info. But you have to Click On The Link to Read It. It will require you to SCROLL down to the section TITLED
Odocoileus virginianus Macrouris4 (Rafinesque)
Plains White-tailed Deer
See That?? PLAINS white tailed deer
Now before you try to claim its "different" I will repost from wiki:
Some
taxonomists have attempted to separate white-tailed deer into a host of
subspecies, based largely in
morphological differences. Genetic studies,[
clarification needed] however, suggest fewer subspecies within the animal's range, as compared to the 30 to 40 subspecies that some scientists described in the last century.
So we are back to your contention that white-tail were sparce in MN and virtually non-existant on the plains and mine that they were common.
Yeah, I think you make this stuff up.