What did William H. Carney do to earn the Medal of Honor?

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Explanation:

It was not awarded to him just because he carried the flag during the battle.  He retrieved the flag from the original fallen flag bearer.  He sustained several wounds while carrying the flag.  He planted the flag in the parapet of Fort Wagner.  Then when the Union army was forced to retreat, he grabbed the flag and once again carried it back to safety with the 54th volunteer regiment of Massachusetts.  When back with the regiment, he finally gave the flag to another volunteer and was quoted as saying "Boys, I did but my duty; the dear old flag never touched the ground".  After this battle, he was honorably discharged due to all the wounds he received during the battle.

That among other things is why is was awarded the Medal of Honor.

d. william mckinley's southern upbringing him win.