The name of Six Grandfathers represents six ancestral deities of the Native Americans, personified as the six directions (cardinal + up and down.) The US and the Lakota Sioux were at war due to US expansion, but then they made a treaty in 1868 promising the Sioux exclusive use of the Black Hills and Six Grandfathers forever.
Of course, US history being what it is, they had another war in 1876, and seized the land in 1877, because of the gold rush. I couldn't find any mention of bounty hunters, but it was a war.
Mount Rushmore was named after Charles E. Rushmore, but it was named by his guide Bill Challis. Charles asked Bill what the mountain was called, and Bill said it didn't have a name, so he named it Mount Rushmore.
The monument at Mount Rushmore was inspired by a Confederate monument in Stone Mountain, Georgia. They got Gutzon Borglum, the same guy who made the other one, to be the sculptor for Mount Rushmore. Gutzon had ties to the KKK, who had funded the Stone Mountain monument, but wasn't technically a member himself.
The original plan for Mount Rushmore was made by Jonah LeRoy "Doane" Robinson, who wanted it to represent "not only the wild grandeur of its local geography but also the triumph of western civilization over that geography through its anthropomorphic representation." Ouch.
Interestingly, he didn't plan to use presidents initially, but instead Old West characters such as Lewis and Clark, Red Cloud, Sacagawea, John C. Fremont, and Crazy Horse. Gutzon shot that down and opted for presidents instead. So basically if it weren't for that guy, we could have had Native Americans on Mount Rushmore.
I couldn't find any evidence of KKK funding for Mount Rushmore, but it did receive private funding, so that's a possibility. Federal funding only game when Gutzon invited Calvin Coolidge to a dedication ceremony, at which he promised it.
So while the truth was almost as bad, this post isn't entirely accurate. You don't like it when the Republicans spread misinformation. Being a communist is no license to do the same.
Source: Wikipedia.
EDIT: After reading the article and Snopes page linked by ZombiFrancis...
- President Grant did order the army not to protect the natives. There were orders that the Black Hills shouldn't be occupied, and he didn't rescind those orders, but he did order the army not to stop miners from going in anyways.
- Bounty hunting was a thing, but there isn't much evidence to point to it being a thing during this war. Much less funded by the government, as they already had soldiers to kill the natives with.
- Gutzon Borglum left the Stone Mountain project due to KKK infighting, and they weren't exactly happy to see him work on Mount Rushmore instead, so it's actually unlikely that they would have funded it - but still a possibility.