The region of Tarren Mill was a region during the Second War. It was to the east of the Southshore region, and west of Alterac. It was the location of the coastal town of Tarren Mill. The Hillsbrad foothills, Southshore region and the region of Tarren Mills make up the bulk of the current Hillsbrad Foothills region.
The mysterious high elves of Silvermoon had sent a contingent of archers south to survey the supposed orcish threat in the area for themselves. Shortly after passing through the Alterac grasslands area of Tarren Mill, the elves were ambushed by Horde troops. Lord Perenolde had betrayed the Alliance, providing the orcs with the routes of the elven strikeforce. The elves were then held in a small prison camp near the northwest area of the region. Lord Terenas fervently hoped to enlist the elves into the Alliance, and asked that the missing warriors were found and delivered to safety. The elves sent a cadre of archers to assist in the mission. They provided plans to construct an elven lumber mill and the sylvan craftsman to operate it during the battle. The mission was a success, and with the safe return of the elves from the orcs, the Council of Silvermoon had resolved to combine the armies of Quel'thalas with those of the Alliance of Lordaeron.