Elrond invites members of each of the free races of Middle Earth to his council. Why is only one kingdom of each of the free races invited to join?
For instance, Gondor represents Men (although there is Rohan as well), the Elves of Mirkwood represent all of the Elves (although there are other Elven kingdoms like Lórien and the Grey Havens) and the Dwarves of Erebor (although there are other Dwarves such as those in the Iron Hills).
Why were the others not invited?