The new collection will contain hundreds of little seen or entirely unknown letters discovered languishing in poorly cataloged archives, tucked away in books or forgotten in attics. One cache of letters turned up in a desk donated to a thrift shop near Hanover, N.H., where they became the focus of a stolen property investigation.

The first volume begins in 1886, with a charming note from 12-year-old Frost to a childhood sweetheart, and follows him through marriage to his wife, Elinor; a hard decade as a farmer in New Hampshire; three years in England; and return home in 1915, when he became a late-blooming literary star with the success of his second collection, “North of Boston.”

It contains little family correspondence (no letters to Elinor are known to survive) and few letters that touch on difficult family matters. But it does vividly show Frost’s deep ambition and confidence — “To be perfectly frank with you I am one of the most notable craftsmen of my time,” he wrote in 1913 — along with a concern to protect his family from intrusions. (“I really like the least her mistakes about Elinor,” he wrote in response to an article by the poet Amy Lowell. “That’s an unpardonable attempt to do her as the conventional helpmeet of genius.”)

The letters show his pleasure in hard-earned fame, but also his resentment. “Twenty years ago I gave some of these people a chance,” he wrote in 1915, referring to his newfound admirers. “I wish I were rich and independent enough to tell them to go to hell.”

The full publication of the letters is the capstone of an arrangement between the Frost estate and Harvard to prepare scholarly editions of Frost’s primary material, in the hopes of inspiring research into a poet whose broad popularity has not always been matched by scholarly attention. The project has not gone entirely smoothly. The 2006 publication of Frost’s notebooks, filled with drafts, fragments and sometimes cryptic aphorisms, was hailed by some critics as the most important Frost release in years but soon came under fierce attack from two scholars charging Mr. Faggen, the volume’s editor, with thousands of transcription errors that turned the poet into a “dyslexic and deranged speller.”

(Harvard released a 2010 paperback making what Mr. Faggen, a professor at Claremont McKenna College, characterized in a recent email as “appropriate changes.”)

That typographical skirmish, however, was nothing compared with the uproar over Ms. Oates’s short story, which drew outrage from Frost family members and the tightknit world of Frost scholars, some of whom gather each year at an informal symposium organized by Lesley Lee Francis, one of the poet’s granddaughters. “It was just mean-spirited and pointless,” said Mr. Sheehy, who together with Mr. Richardson prepared a 14-page document challenging the story’s factual underpinnings.