Board Thread:Lore/@comment-97.125.181.26-20150622022353/@comment-26065062-20150622124217

Actually King Thingol Greymantle of Doriath got the Silmaril from Beren as a brideprice for his daughter Luthien and asked one of the two greatest dwarven smiths of all time, Telchar to put it into the Nauglamir, the necklace of the dwarves. But the dwarves wanted the Silmaril, so they kept it, so the elves hunted them all down except for one, which managed to escape and tell the King of Nogrod a slightly exxagerated story of what happened to make it seem like the elves' fault, so he sent a great force of angry dwarves to attack Doriath. Many elves and dwarves were killed in the process, as well as Thingol. The dwarves stole the Nauglamir with the Silmaril in it and went back to Nogrod, happy about the massacre that they caused. After the departure of Melian, Beren Encalmion killed them all with his army of Laiquendi.

That is the main reason why elves and dwarves hate each other most of the time.