Sauron

Sauron is the dark lord of Middle-Earth and is the forger and founder of the one ring.

Sauron and the orcs
Sauron corruped the 9 men with their rings and turned them into the Nazgul. He also made the orcs of Mordor who fight in the war of the ring, they are beaten by men because of their weak armour. Also as seen in the two towers the orcs are also said by Legolas that they have weak armour and are easy to kill with arrows.

Sauron and the one ring
Sauron was the forger of the one ring. He used the ring to try and wipe out the race of men and elves in the men and elve alliance war. He is killed by Isildur with the sword of kings. Well thats what they thought but he is remade and is his eye is placed on te tower of Barad-Dur this is also a dungeon for dark people (like Gollum) they torture people in there until they get what they want hence why Gollum is tortured to the point where he tells the Orcs the location of the ring. Sauron is defeated in the return of the king when Frodo Baggins tosses the one ring into the fiery casum of Mount Doom where it came from. Sauron is supposidly seen in The Hobbit there are a lot of different arguments on that topic as itis unknown until the hobbit 2 desolation of Smaug is made. Radoghast is seen to have seen someone possessing a Mogul blade who tries to kill him but fails to do so, and radoghast gives the morgul blade to Gandalf and he shows it to the elve gathering in Rivendell.