Tulkas was the most warlike of the Valar and the last of them to descend into Arda, coming to the aid of the others when he heard of their war with Melkor. Melkor fled before him, and the Spring of Arda was begun.
After the Two Lamps were erected and the Valar had made their first dwelling at Almaren, Tulkas wedded Nessa in a great feast. Being weary and content he slept, and Melkor decided his hour to retaliate had come.
Tulkas is described as delighting in wrestling and contests of strength. He wields no weapon, and rides no steed. As he cares little about either past or future, he is not a good councillor, but nonetheless a very hardy friend. He is described as being slow to wrath, but also slow to forgive—for that reason, he was one of the Valar that opposed the release of Melkor.
Tulkas also tends to be impatient; before the Awakening of the Elves he urged the other Valar to wage war against Melkor. After the Darkening of Valinor he also hurried Fëanor to take a decision about surrendering the Silmarils.