Elanor was born on the second anniversary of the destruction of the Ring (which took place on 25 March III 3019). Her birth therefore also coincided with the exact beginning of the Fourth Age, according to the calendars of the Dúnedain (though the Hobbits themselves simply continued to count years according to the Shire-reckoning).

IV 61 was the year in which Elanor's mother Rose died, and in which her father Samwise later left the Shire and, according to tradition, passed across the Sea. He gave the Red Book to Elanor before he departed, and this is the last mention of her in any record. She would only have been 61 years old at that time, and it is likely that she lived for several more decades.

Elanor's name was given at the suggestion of Frodo Baggins, recalling the golden elanor flowers seen by the Fellowship of the Ring on Cerin Amroth in Lórien.