Basilisk was home to the Basiliskans, an intelligent lizardspecies. They were the creators of the Basilisk War Droids, that were rumored to be modeled after themselves. During their war with the Mandalorians around the year 3,997 BBY, the Basiliskans chemically poisoned their own planet, in a last effort to defeat their conquerors. Despite receiving Jedi and Republic reinforcements under Sidrona Diath at the Battle of Basilisk, the Mandalorians conquered the planet and enslaved the remaining Basiliskans.
After the war, the Mandalorians found a new use for the Basiliskans. With their tough hides and claws, with which they could be trained, and their intelligence, the Mandalorians used them as weapons for aerial and ground fighting during later wars. Because of this the Basiliskans degenerated and became nothing more than beasts. As such, they were re-named the Lagartoz War Dragons.