The battle in which the Noldor attacked the Teleri. When the Noldor decided to leave Valinor and asked for their ships, the Teleri refused to join, and even tried to talk them out of leaving. As a result, many of them were cruelly slain in the Kinslaying at their chief city of Alqualondë, or Swan Harbour. This was the first of three Kinslayings that were committed by Fëanor's people against their fellow Elves.
Dwellings of the Valar: Ulmo "He loved not high words and concourse of folk, and in those deep waters moveless and empty he purposed to dwell, leaving the governance of the Great and lesser seas to Ossë and Ónen his vassals. Yet ever of his magic deep in his outmost sea-halls of Ulmonan he controlled the faint stirrings of the Shadowy Sea, and the lakes and springs and rivers of the world." “The Coming of the Valar” - The Book of Lost Tales (part. 1) - HoME - J.R.R. Tolkien