Que raça é Sauron e ele estava envolvido na criação dos anéis de poder?

Sauron era um Maia . Sua raça era Ainur .

There was Eru, the One, who in Arda is called Ilúvatar; and he made first the Ainur, the Holy Ones, that were the offspring of his thought...
_{-- First words of the Ainulindalë}

They were the primordial spirits, who existed with Ilúvatar, and with him created the world through The Ainulindalë, The Music of the Ainur. After the creation of Arda, many of the Ainur descended into it to guide and order its growth; of these there were fifteen more powerful than the rest.
_{-- The Silmarillion: Ainulindalë}

Before the creation of Ea, Sauron was one of the countless lesser Ainur spirits created by Eru Iluvatar, known as the Maia. At this time he was known as Mairon the Admirable, and partook in the Ainulindale, or Music of the Ainur. However, unlike many other spirits, Mairon did not align himself with Melkor upon the introduction of his discord themes, and thus, did not initially fall under his sway.
_{-- The Silmarillion, Ainulindalë (The Music of the Ainur)}

A raça de Sauron é Maia.

Among those of his servants that have names the greatest was that spirit whom the Eldar called Sauron, or Gorthaur the Cruel. In his beginning he was of the Maiar of Aulë, and he remained mighty in the lore of that people. In all the deeds of Melkor the Morgoth upon Arda, in his vast works and in the deceits of his cunning, Sauron had a part...

- Ainulindalë - Dos Inimigos

Sauron era originalmente o tenente de Melkor, e um ser menor:

And Melkor made also a fortress and armoury not far from the north-western shores of the sea, to resist any assault that might come from Aman. That stronghold was commanded by Sauron, lieutenant of Melkor...

- Quenta Silmarillion - Capítulo 3 - Da vinda dos elfos e do cativeiro de Melkor

Os Maiar são menores Ainur:

With the Valar came other spirits whose being also began before the World, of the same order as the Valar but of less degree. These are the Maiar, the people of the Valar, and their servants and helpers.

- Ainulindalë - Do Maiar

Sauron criou o próprio One Ring, a fim de obter controle sobre os usuários de todos os outros anéis.

Now the Elves made many rings; but secretly Sauron made One Ring to rule all the others...

Como ele colocou muito do seu poder no Anel, sua destruição foi essencial para derrotá-lo:

And much of the strength and will of Sauron passed into that One Ring; for the power of the Elven-rings was very great, and that which should govern them must be a thing of surpassing potency...