The Windan were a people of the Avari elves that had followed Tareg to the Westlands and had come to the lands of Rhûn, Rhovanion, and finally Eriador and Beleriand. The Eölrim were one of their clans that had moved into Beleriand while the Mountain-elves of Mirkwood descended from those Windan who did not cross the Hithaeglir. The Hvettir of southern Lindon were seen as a remnant of Eöl's folk. They were descended from the Tatyar, and thus distant relatives of the Noldor.
The Windan were a relatively simple culture of cave-dwellers and mountaineers. They settled in small communities in the mountains and foothills. Through contacts with the dwarves and Sindar they learned metalwork and soon became master smiths; the Eölrim in particular were among the greatest smiths of Middle-earth and could compete with their distant relations, the Noldor. Those Windan who settled in the Mountains of Mirkwood became used to the Wood-elves and adopted some of their customs, although they tended to stay among their own kindred and only grundgingly accepted Thranduil's overlordship.
The Windan were small by elvish standards, sometimes barely reaching 5'7". They had often a skin of ruddy, swart or dark hue, though more silvery or ivory complexions were not quite uncommon, and mostly dark brown or blueish black hair.
The Windan were the descendants of Hwendi-Avari who had followed the host of Tareg after the Battle of Palisor. While most of them stayed in the Mountains of Mirkwood, a few of their clans had moved towards into Eriador and the south of Beleriand, where they inhabited Nan Elmoth (the home of Eol) and Taur-im-Duinath. The Windan were the first (and for many centuries only) Avari to be encountered by the Noldorin Exiles, and the Windan felt great jealousy toward their more exalted kindred, as seen in Eol's hostility toward his "neighbors", the Sons of Feanor. During the War of Wrath, almost all the Windan of Beleriand perished, save for a single surviving clan that became the Hvettir of Lindon.
The Windan spoke an Avarin dialect called Windëa.