ummmm....yea, of course they were. General James Longstreet had a record of the union using the hand grenades on his men. "Our men were firing at the union soldiers last i saw of 'em. After the men lost hope, we jumped in a low trench, where we thought we would take cover. Just as we reloaded, we saw the sky turn a dark, smokey, black. I saw my men die around me, as shrapnel plunged into their legs. i gave my men an order to put ladders up the trench to attack the union dogs. Just then, i sounded an order to retreat, we had lost, but the battle had not begun."

-James Longstreet

More than 5 recorded documents were found on both union and confederate strategies, giving you substantial proof that there were in fact grenades in the civil war.