A species. Or, well, was.
Ever notice how he's THE Grinch? There used to be many of them. They weren't always so evil, the Grinches. A peaceful lot, really. Until those damned Whos came. The Grinches lived in harmony with nature, celebrated their own holidays built around the natural cycles, then came the warmongers.
At first, things were okay. The Whos took little from the world, just enough to build their homes, feed their families. Then came expansion. Those mountains were once dense with trees, felled to build Whoville. Roast Beast? Native hogs, hunted to near extinction. The Grinches? Enslaved. They rioted, and the children were taken. This did not stop them, so those bastards put each to the sword. The waters of Whoville ran red that night.
One child survived, and later escaped. He fled to the mountains, and devoted himself to making the Whos pay for what they had done.
It was not the magic of Christmas that made his heart grow three times that day. It was madness. He failed. He could not break them, as they had broken his people. They were too damned resilient, too damned established.
You ever realize the story ends there? With him "making peace"? Because that was not peace. That was suicide. The Whos of Whoville finished their extermination, and a noble species will never return...
"Grinch, Grinch, and Grinch"