The Spartoi: dragon teeth soldiers [Greek mythology]
When the Greek hero Kadmos (Cadmus in Latin) arrived in Boeotia to find Europa, he attempted to slaughter a cow to make an offering for the goddess Athena, and ordered his soldiers to bring water.
Unbeknownst to the soldiers, the well was guarded by a horrible dragon, supposedly a son of war-like Ares himself. The monstrous creature killed most of his men until Kadmos arrived. Being quite the warrior himself, he managed to slay it. Then Athena gave him the advice to pull the teeth from the dragon's corpse and plant them in the fertile soil as if they were plants. Not one to question the will of the gods, Kadmos obliged and sowed half of the teeth like a farmer sows grain.
Human-like creatures grew from them and emerged from the soil fully armed. They were called Sparti or Spartoi, meaning 'sown' or 'sown ones'. They are also sometimes referred to as ‘earthborn’ or ‘the earthborn men’. Kadmos picked up some rocks and flung them at the strange creatures before them, confusing the Spartoi, who assumed that their siblings had turned on them. In a fit of rage, the creatures pounced on each other until all but five were slain. These survivors were named Pelorus, Hyperenor, Chthonius, Udaeus and Echion.
Whether these soldiers were fully human is debatable (the magic of the gods doesn't have to follow the rules of biology, after all) but they did eventually marry human women. Modern artists often give them a more fantastical design to underline their monstrous origin, often making them tooth-like creatures or magically animated skeletons. In older illustrations, the Spartoi are usually depicted as human soldiers.
The war god Ares was not pleased at the killing of what technically amounted to his grandchildren. He enslaved Kadmos as punishment, but set him free after eight years.
The other half of the dragon's teeth, however, were kept and eventually ended up in the possession of the wicked king Aeetes, ruler of the Colchians. When Jason of the Argonauts landed there, he was challenged by the king to yoke the two fire-breathing bulls of Hephaestos, and to sow the remaining dragon teeth. When Jason did so, a new batch of armed Spartoi emerged, just like in the past, armed with spears, shields and helmets. And like their siblings, these creatures had a violent nature and lusted for battle.
Repeating the actions of his predecessor, Jason hid from the Spartoi and pelted them with rocks. Once again, the creatures began to slaughter one another until only a few remained, at which point Jason emerged from his hiding place and killed the survivors without mercy, even those who didn’t have enough time to fully come out of the soil. Soon, every earthborn soldier was left dead, their blood flowing back into the ground that had birthed them.
Pseudo-Apollodorus, Bibliotheca, book 3, chapter 4, which you can read here.
Pseudo-Apollodorus, Bibliotheca, book 1, chapter 9, which you can read here.
Apollonius Rhodius, Argonautica, book 3, lines 396-422, lines 1163-1190, lines 1340-1407.
(Image source 1: Darko Kreculj on Artstation, illustration for Project Icelus)
(Image source 2: Cadmus and Athena, by Jacob Jordaens)
