No, the NRA Didn't Help Protect Former Slaves from the Democrats

During the just completed 2018 convention, the National Rifle Association helped spread some false history using Trump supporters Diamond & Silk. Watch:


This claim about the NRA has been debunked several times. The NRA was founded by two Union military veterans to help improve marksmanship. There isn’t any evidence that the NRA assisted post-Civil War freed slaves against the KKK or Democrats or any white aggression. Supporters of the NRA offer this claim without any historical evidence.
At the time, the Democrat party was the party of Jim Crow. However, the NRA claim appears to be made up out of thin air. To fact check the claim, I reviewed the founding documents of the NRA, the biographies of the founders, and historical descriptions of the organization, especially in the South. According to the NRA’s founding document, the aims of the association related to rifle practice:

AIMS OF THE ASSOCIATION
The main aim of the Association is the encouragement of rifle practice throughout this State and the United States.
They also desire to promote the establishment of ranges throughout the State, and the issue of ammunition, target, and other appurtenances required for their use with offering of prizes both by the State, and by individuals, to the best marksmen. They also seek to build up local of a similar character to their own, which while under official supervision to ensure then proper, yet will be so popular in their character as to secure success.

Over the years, I have asked those who say the NRA was founded to help protect former slaves (e.g., David Barton) for supporting evidence. I have yet to seen anything remotely relevant to the claim.
This is the first time I have seen the claim from the NRA and they should provide evidence or retract it immediately.