This was only a couple generations removed from us. Like, my grandfather was a kid (elsewhere) when this happened.

The picture of the guns makes it look like a primary armed rebellion but apparently it was initially peaceful, and when state troops intervened, they confiscated guns from both strikers and the "armed guards" sent to break the strike.

https://en.wikipedia.org/wiki/Paint_Creek%E2%80%93Cabin_Creek_strike_of_1912

The union called a strike for April 18, 1912.[4] Their demands were:

1. That the operators accept and recognize the union.

2. That the miners' right to free speech and peaceable assembly be restored.

3. That black-listing discharged workers be stopped.

4. That compulsory trading at company stores be ended.

5. That cribbing be discontinued and that 2,000 pounds of mined coal constitute a ton. That scales be installed at mines to weigh the tonnage of the miners.

6. That miners be allowed to employ their own check-weighmen to check against the weights found by company check-weighmen, as provided by law.

7. That the two check-weighmen determine all docking penalties.