Where did the ring come from in Lord of the Rings?

The One Ring was made by the Dark Lord Sauron. He made it to control the other Great Rings of Power, which he had helped the Elves create. He put a good portion of his own soul into the Ring; this power would give his Ring dominion over the others. This Ring was seductive, powerful, and possessed, and it could possess its wearer. The only Great Rings it did not have power over were the Elf Rings, because they had never been touched by Sauron.

The One Ring could only be destroyed in the fires of the Cracks of Doom in Mount Orodruin (Mount Doom) in Mordor, for that was where Sauron had made it.

The other Great Rings were made in the Elven realm of Eregion.