This article is based on fan speculation
"In the darkest era of our history, the Sands of Evil spread throughout Minecraftia with hordes of demons following it. The brave Skylords, led by Verigan and his son Karpath marched to meet this threat, and in one of the most bloodiest wars in Minecraftian history, they drove the sand back to where it came from."
-History Wall
The Great Sand War was a time when Verigan Antioch, his son Karpath and others fought against The Sands, a terrible disease.
Plot
The Sand War took place one hundred years ago in Minecraftia. The Sands were a disease which spread throughout Minecraftia. Land went dry and people died of hunger and thirst. Led by a legendary hero, Verigan, the people of Minecraftia fought back and built The Wall to enclose the Sands and halt the spread of the desert. However, then terrible, ancient Evil arose from the Sands and threatened to destroy everything. Verigan and his son, Karpath, killed the evil monster and sealed it away under the Desert. Verigan was unfortunately killed in the battle. Karpath returned to Minecraftia and founded the Crimson Cross and established the Templars. Karpath soon vanished without a trace and was never seen again. The Templars still await his return.
Many years later, the Evil was unleashed again, and a new Sand War brews, with Israphel and his cult attempting to undermine their main enemies: Xephos, Honeydew, and the son of Karpath: Knight Peculier. As these heroes have traveled, they've gained many allies: The last templar, Templar Adaephon, Knight Peculier's uncle, his sister, Isabel Peculier, and the pirates of BBQ Bay, and the flying ship of the Skylords, the Skyhold, along with the Skylords themselves. They have befriended the few remaining dwarves of Stoneholm, the Shiplord Hubert, and the two wizards Fumblemore and Swampy Bogbeard.