Oct 20 2021, 3:22pm
I wish I could quote John D. Rateliff's The History of The Hobbit on the subjects of the Shire Reckoning, Midsummer's Day and Durin's Day, but I don't own a copy and it's been too long since I've read the book (borrowed from our local library system).
The Hobbit and the Shire Reckoning
I do have a copy of Douglas A. Anderson's The Annotated Hobbit. In Chapter 3, "A Short Rest", on the topic of midsummer Anderson notes:
The reference here to midsummer is ambiguous. It could mean the summer solstice, about June 21, or it could mean June 24, which is traditionally Mid-summer Day, the feast of St. John the Baptist. Both dates are supported by the Oxford English Dictionary.
Karen Wynn Fonstad, in her chronology of The Hobbit as printed in the revised edition of The Atlas of Middle-earth (1991), interpreted the midsummer reference as synonymous with the summer solstice and also as equivalent with Mid-year's Day from the Shire Calendar in Appendix D of The Lord of the Rings. This latter correspondence is supported by the statement in Appendix A that Aragorn and Arwen were married "at Midsummer in the year of the Fall of Sauron," and in Appendix B, "The Tale of Years," where the wedding is specified as having taken place on "Mid-year's Day." Yet in Appendix D, it is written that "it appears, however, that Mid-year's Day was intended to correspond as nearly as possible to the summer solstice" -- which suggests that it may not necessarily have been on the actual solstice.
Douglas Anderson has nothing substantial to say on the date of the Durin's Day of the year 2941 (Third Age).
(This post was edited by Otaku-sempai on Oct 20 2021, 3:31pm)