The Sword of Summer is a young-adult fantasy novel based on Norse mythology written by American author Rick Riordan.

The Sword of Summer received positive reviews from critics, who praised its plot, humor, the inclusion of diverse characters, and mature themes, but also noted its failure to rise above the author's previous work.

During the quest, Magnus experiences dream-visions of Loki, and once even of the goddess Hel offering to reunite him with his late mother—a proposal he struggles to refuse.

[1] The first line of the prophecy was initially taken as confirmation that Magnus was unfit for duty as an einherjar; later, Odin interprets it to mean that Loki chose the wrong hero to manipulate.

[1] During Riordan's book tour for The House of Hades, he announced that he was writing a Norse mythology series that would take place in Boston.

He also stated that his plans for the setting were unrelated to his recent move to the city, although living in Boston made researching for the series less difficult.

[2] On September 23, 2014, Riordan broadcast a webcast from the Empire State Building and announced the name of the series: Magnus Chase and the Gods of Asgard.

[5] To prepare readers for the new book, Riordan posted images of Norse vocabulary words on his Twitter account starting August 28, 2015, along with the hashtag #norsecrashcourse.

[7][8][9][10] An online myth-writing competition was sponsored by Scholastic just before the novel's publication, with the grand prize of a "virtual visit" from Rick Riordan.

[11] Finally, Riordan signed 10,000 copies of The Sword of Summer, to be distributed on Black Friday at Barnes & Noble stores nationwide, as yet another massive advertising campaign.

[15] To date, editions have been published in English, Spanish, Italian, Portuguese, French, Polish, Turkish, Dutch, Bulgarian, and Finnish.

"[22] While reviewer Jody Mitori said Riordan's pop culture "references may date the book in years to come", she went on to assert that "for now, they make the trek entertaining".

Author Cassandra Clare's review, praised "Riordan's effervescent world-building", in addition to the novel's humour and breakneck plot.

"[1] KidsReads's review praised the characters and their development, saying "Magnus Chase feels fresh and exciting" even with its oft-used mythological themes.

[26] Reviewers such as Publishers Weekly have praised the book, saying, "Riordan plays much of the material for laughs...and brings the Norse gods into the 21st century...

A similar review from the St. Louis Post-Dispatch asserted that "at nearly 500 pages, Sword of Summer is too long" and loses some of its charms from the overuse of "quests-within-a-quest".

[30][31][32] Other reviewers have shown interest in Riordan's choice to kill his main character and other signs of his newest story being more mature than the famous Percy Jackson & the Olympians.

[31][32] Kirkus praised Riordan's interesting choice to make the main female protagonist, Samirah al-Abbas, happily betrothed—and thus "blessedly free of romantic tension" with Magnus.