A/N: First, a word of explanation. The idea for this fic has been bouncing around inside my head for nearly a year now. I certainly couldn't have written it last summer when it first occurred to me, but having started now, I find I can't stop. The inspiration for this story comes from a number of different things: Orson Scott Card's Ender's Game, Star Wars, Doctor Who, and my own experiences as a graduate teaching assistant. But mostly from How to Train Your Dragon, which belongs to Cressida Cowell and DreamWorks Animation. I hope this fic is as much fun to read as it is to write.

Prologue:

They came from across the stars, from a far-away world the humans knew only as the Nest. Astronomers had observed it for years, dreaming of perhaps exploring it someday and speculating about whether its surface could support life. By the time they discovered what its surface actually supported, it was too late.

Everyone knew about the War; of course they did. Even those who lived in rural areas far from the densely-populated cities and urban centers had felt the effects of the initial invasion: fear running like a flood through the streets while the world burned, mighty cities reduced to rubble and strong men to whimpering husks of humanity in the face of imminent defeat. Dragons landed in wave after unstoppable wave, coming directly from the Nest, punching through Earth's pathetic shield of atmosphere to wreak destruction on the unsuspecting populace below.

San Francisco was the first hit; it fell in a day. From its blackened ruins, fire leaped forth to scorch the hardened deserts of the western states and devour the Great Plains, reaping a bitter harvest of ash and smoke. The death toll, so high after the first strike, only rose in the weeks of chaos that followed. Those not directly affected by the initial attacks soon succumbed to the privation and sickness that followed in the wake of crumbling infrastructure and lack of resources.

The Americas eventually capitulated, overwhelmed too quickly to fight back. The Pacific Islands were hit hard; New Zealand and Taiwan were overrun while the islands of Japan burned. But the inhabitants of central Asia, Europe, and Australia, in the little time they had, banded together to fight back.

It was difficult; lingering political prejudices nearly grounded the fighter pilots before they could take off, and the inexorable threat of terror descending from the skies had left smaller countries cowering in knock-kneed impotence. Somehow, the few countries left had managed it, beating the invaders back bit by bit until the tide turned. The final battle was an all-for-it, win-or-die confrontation far above the planet's surface, stubborn humanity against the unknowable foe, the humans united by terror and desperation in equal measure, giving no quarter and taking none. They were led by a Scandinavian pilot, a man renowned for an insane mixture of reckless courage and unbelievable skill. His name was Finn Hofferson, known to his men as Fearless. Those invaders not killed outright slunk back to their world on the other side of the solar system, metaphorical tails between their legs, while the shocked and scattered remnant of humanity rose from the devastation to rebuild. The battle was won, but at a great cost in lives. After striking the final, decisive blow, Finn Hofferson was never seen again, presumed dead or captured. In his absence, the men he had led returned to Earth to mourn, to rebuild, and ultimately, to rejoice at their victory.

But before the rejoicing came the sorrow.

The death toll was catastrophic; like strong forests blasted by wildfire, the young and strong had been cut down with the old and weak. There was not a family on Earth not affected, and whole countries were decimated in the harshest reminder of frailty possible.

But from the ashes the phoenix arose, hope blossoming with the turning of the seasons.

Everything on Earth changed after that, and not just the ecology. At first, smaller countries and states, unable to rebuild on their own limited resources, joined in alliance under strong rulers; then larger countries, fearing for their political well-being, banded into confederacies continent-wide and millions strong. Firm political rulers, democratically elected, soon replaced weak hereditary monarchs and the idealistic schisms of theocratic governments. Economic patterns shifted, regions with a surplus of resources first encouraged, then mandated to aid those with less. Dissident voices were drowned out in the clamor for global politics and economy, the needy majority outweighing the cautious minority.

Twenty years after the first invasion, the habitable parts of the planet were united under a planetary ruler: the Premier, chief of state and ultimate political authority on Earth. This august individual, summarily elected and serving a lengthy term of service, reshaped the globe, raising it to a new order, one that turned on centralized government and strong military rule.

Along with the control of their trade, regional centers dedicated their younger generation to the creation of the Planetary Defense Corps, a body dedicated to protection and prevention on the ground, in the sky, and beyond.

Because the Premier and the people he ruled, every last man, woman, and child on Earth, knew with a dreaded certainty that the invaders would eventually be back. It was only a question of when.

A/N: Thanks for reading, and please let me know what you think. Updates will probably be weekly, depending on how much time I have between working multiple jobs. 'Til the next chapter!