Os Dúnedain Rangers estavam guardando o Condado por algum tempo quando os Nazggl chegaram e entraram na terra dos Hobbits durante sua caçada ao Anel. Como os Nazgull passaram pelas patrulhas de fronteira ou os Rangers desconheciam sua presença no Condado?
Isso é respondido na entrada Tale of Years de 22 e em setembro de 3018 (retorno do rei, apêndice B):
The Black Riders reach Sarn Ford at evening; they drive off the guard of Rangers.
E para o 23, em setembro, o 3018:
Four Riders enter the Shire before dawn. The others pursue the Rangers eastward, and then return to watch the Greenway.
Há mais informações sobre isso em Contos inacabados, A Caçada ao Anel, e eu dou a passagem na íntegra:
Night was waning on the twenty-second day of September when drawing together again they came to Sarn Ford and the southernmost borders of the Shire. They found them guarded for the Rangers barred their way. But this was a task beyond the power of the Dúnedain; and maybe it would still have proved so even if their captain, Aragorn, had been with them. But he was away to the north, upon the East Road near Bree; and the hearts even of the Dúnedain misgave them. Some fled northward, hoping to bear news to Aragorn, but they were pursued and slain or driven away into the wild. Some still dared to bar the ford, and held it while day lasted, but at night the Lord of Morgul swept them away, and the Black Riders passed into the Shire; and ere the cocks crowed in the small hours of the twenty-third day of September some were riding north through the land, even as Gandalf upon Shadowfax was riding over Rohan far behind.
Por isso, os Dunedain estavam lá, mas foram afastados por cinco dos Nazggl para permitir que os outros quatro entrassem.