The War of the Jewels was a war that started when Morgoth stole the Silmarils from Fëanor, the elf who created them. Fëanor, subsequently, declared war on Morgoth and vowed that he would not rest until his precious Silmarils were recovered, using even the name of Ilúvatar in his foul and foolish oath. Convincing most of the Noldor to leave Valinor and the "dictatorial" Valar behind and to journey back to Beleriand, Fëanor left Valinor with a great host using the stolen ships of the Teleri obtained from the Kinslaying. From there, the War of the Great Jewels truly began.