Ainur

The first and mightiest of ILLUVITAR'S creations. They sprung from his thought, and each had great understanding of that part of Illuvitar's mind from which they sprung.
Fourteen of them would become the mightiest and be known as the VALAR , and work on the final crafting and then the ongoing care of Middle Earth.
One of their number, MELKOR, led a rebellion off and on throughout the first ages. Adding discord to the @SONG OF ILLUVITAR , and then on other occasions during the crafting of Middle Earth. He would often repent, and was eventually subdued in the WAR OF THE VALAR , but rebelled again stealing the SIMARILS , which led to the Elves leaving the BLESSED REALM , and going back to Middle Earth to claim their prize.
The rest of the Valar remained faithful to Illuvitar and his plan.