Walter Miller was a prolific writer of science fiction short stories; by 1955 he had published over 30 stories in such magazines as Astounding Science Fiction, Amazing Stories, and Fantastic Adventures. Significant themes of his stories included loss of scientific knowledge or "socio-technological regression and its presumed antithesis, continued technological advance", its preservation through oral transmission, the guardianship of archives by priests, and "that side of [human] behavior which can only be termed religious." These thematic elements, combined with the growing subgenre of the "post-disaster" story and Miller's own World War II experiences, set the stage for the short story that would become the opening section of A Canticle for Leibowitz.
During World War II, Miller served as part of a bomber crew that participated in the destruction of the ancient Roman Catholic monastery at Monte Cassino, Italy founded by St. Benedict in the 6th century. This experience impressed him enough to write, a decade later, the short story "A Canticle for Leibowitz" about an order of monks whose abbey springs from the destroyed world around it. The story, which would evolve into "Fiat Homo"—the first part of the novel—was published in the April 1955 edition of The Magazine of Fantasy and Science Fiction (F&SF). Although not originally intended as a serialization, the saga continued in "And the Light Is Risen", which was published in August 1956 (also in F&SF). That work would later grow into "Fiat Lux". It was while writing the third "novelette", "The Last Canticle", for magazine publication in February of the following year that Miller realized he was really completing a novel: "Only after I had written the first two and was working on the third did it dawn on me that this isn't three novelettes, it's a novel. And I converted it."
The publication of the three Canticle stories, along with Miller's "The Lineman", in The Magazine of Fantasy and Science Fiction marked a significant evolution in the writer's craft. Under the editorship of Anthony Boucher, F&SF possessed a reputation for publishing works with "careful writing and characterization." Walker Percy considered the magazine "high-class sci-fi pulp". The appearance of these stories in the magazine is indicative of the direction Miller's writing had taken toward "'human' stories, less crowded with incident, more concerned with values".
For the novelization, Miller did not simply collate the three short stories. He changed the title and the names of some characters, added new characters, changed the nature and prominence of existing characters, and added Latin passages. These revisions affected the religious and recurrence themes of the story, resulting in "decided improvements" over the magazine versions.
The Latin phrases in the novel related to Roman Catholic Church practices, rituals and official communications. Susan Olsen writes that Miller did not include the Latin phrases just to "add dignity" to the work, but to emphasize its religious themes, making it consonant with the tradition of Judeo-Christian writings.
Changing the name of the abbot of the first part from "Father Juan" to "Abbot Arkos" strengthened the cyclical/recurrence motif, since the name of the first abbot encountered, "Arkos", begins with the first letter of the Latin alphabet and the name of the last abbot, "Zerchi", begins with the last letter. Miller also expanded scenes, increasing their importance: for instance, the initial encounter between Brother Francis and Abbot Arkos in "Fiat Homo" grew from two pages in the short story to eight pages in the novel. Abbot Arkos was shown to possess doubts and uncertainty, unlike the dogmatism of Father Juan.
Miller also used the adaptation process to add a significant layer of complexity to the story. Walker Percy recognized this dimension of the novel, which he compared to a "cipher, a coded message, a book in a strange language". David Seed deemed the novel "charged with half-concealed meaning", an intricacy that seems to have been added as Miller was revising the stories for publication as a novel. Decoding messages such as this is an important activity in Miller's works, both in A Canticle for Leibowitz and his short stories. For example, in the original version of "Fiat Homo" Miller limits his "wordplay" to an explicit symbolism involving the letter "V" and Brother Francis's "Voice/Vocation" during Francis's encounter with the wandering pilgrim. In the novel, however, "Miller reserves such symbolistic cross-references to the more intellectual analysts and builds a comedy of incomprehension around Francis."
Miller's extensive experience in writing for science fiction magazines contributed to his achievement with A Canticle for Leibowitz. His strengths were with the medium lengths of the short story, novelette, and short novel, where he effectively combined character, action, and import. The success of this full-length novel rests on its tripartite structure: each section is "short novel size, with counterpoint, motifs, and allusions making up for the lack of more ordinary means of continuity".
The novel was published by J. B. Lippincott & Co. as a hardcover in 1960 (although the copyright is 1959), and demand for the book was sufficient to prompt two reprints within the first year. In 1961 it was awarded the Hugo Award for Best Novel by The World Science Fiction Convention. Since then A Canticle for Leibowitz has had new editions and reprints issued in paperback and hardcover more than 40 times, and has never been out of print. It regularly appears on "best of" lists and has been recognized three times with Locus Poll Awards for best all-time science fiction novel.
A Canticle for Leibowitz opens 600 years after 20th century civilization has been destroyed by a global nuclear war, known as the "Flame Deluge". The text reveals that as a result of the war there was a violent backlash against the culture of advanced knowledge and technology that had led to the development of nuclear weapons. During this backlash, called the "Simplification", anyone of learning, and eventually anyone who could even read, was likely to be killed by rampaging mobs, who proudly took on the name of "Simpletons". Illiteracy became almost universal, and books were destroyed en masse.
Isaac Edward Leibowitz had been a Jewish electrical engineer working for the United States military. Surviving the war, he became dedicated to preserving knowledge by hiding books, smuggling them to safety (booklegging), memorizing, and copying them. Eventually, whether by Leibowitz' intention or simply though the sanctification of repetition, his supporters and followers became a monastic order, the "Albertian Order of Leibowitz", dedicated to preserving knowledge. The Order's abbey is located in the American southwestern desert, near the military base where Leibowitz had worked before the war, on an old road that may have been "a portion of the shortest route from the Great Salt Lake to Old El Paso". Leibowitz was eventually betrayed and martyred. Later beatified by the Roman Catholic Church, he became a candidate for sainthood.
Centuries after his death, the abbey is still preserving the "Memorabilia", the collected writings that have survived the Flame Deluge and the Simplification, in the hope that they will help future generations reclaim forgotten science.
The story is structured in three parts titled: "Fiat Homo", "Fiat Lux", and "Fiat Voluntas Tua". The parts are separated by periods of six centuries each.
In the 26th century, a 17-year-old novice named Brother Francis Gerard is on a vigil in the desert. While searching for a rock to complete a shelter, Brother Francis encounters a Wanderer, apparently looking for the abbey, who inscribes Hebrew on a rock that appears the perfect fit for the shelter. When Brother Francis removes the rock, he discovers the entrance to an ancient fallout shelter containing "relics", such as handwritten notes on crumbling memo pads bearing cryptic texts resembling a 20th-century shopping list. He soon realizes that these notes appear to have been written by Leibowitz, his order's founder. The discovery of the ancient documents causes an uproar at the monastery, as the other monks speculate that the relics once belonged to Leibowitz. Brother Francis' account of the Wanderer, who ultimately never turned up at the abbey, is also greatly embellished by the other monks amid rumours that he was an apparition of Leibowitz himself; Francis strenuously denies the embellishments, but equally persistently refuses to deny that the encounter occurred, despite the lack of other witnesses. Abbot Arkos, the head of the monastery, worries that the discovery of so many potentially holy relics in such a short period may cause delays in Leibowitz's canonization process. Francis is banished back to the desert to complete his vigil and defuse the sensationalism.
Many years later, the abbey is visited by Monsignors Aguerra (God's Advocate) and Flaught (the Devil's Advocate), the Church's investigators in the case for Leibowitz's sainthood. Leibowitz is eventually canonized as Saint Leibowitz – based partly on the evidence Francis discovered in the shelter – and Brother Francis is sent to New Rome to represent the Order at the canonization Mass. He takes the documents found in the shelter and an illumination of one of the documents on which he has spent years working, as a gift to the Pope.
En route, he is robbed and his illumination taken. Francis completes the journey to New Rome and is granted an audience with the Pope, who was modeled after Pope John XXIII. Francis presents the Pope with the remaining documents, and the Pope comforts Francis by giving him gold with which to ransom back the illumination; however, Francis is killed during his return trip by a group of "The Pope's Children" (an affectionate name for the people who have been so severely affected by the genetic mutation caused by radiation that they are subhuman in both intelligence and capacity for reason), receiving an arrow in the face. The Wanderer discovers and buries Francis' body. (The book then focuses on the vultures who were denied their meal; they fly over the Great Plains and find much food near the Red River until a city-state, based in Texarkana, rises.)
In 3174, the Albertian Order of St. Leibowitz is still preserving the half-understood knowledge from before the Flame Deluge and the subsequent Age of Simplification. The new Dark Age is ending, however, and a new Renaissance is beginning. Thon Taddeo Pfardentrott, a highly regarded secular scholar, is sent by his cousin Hannegan, Mayor of Texarkana, to the abbey. Thon Taddeo, frequently compared to Galileo, is interested in the Order's preserved collection of Memorabilia.
At the abbey, Brother Kornhoer, a talented engineer, has just finished work on a "generator of electrical essences", a treadmill-powered electrical generator that powers an arc lamp. He gives credit for the generator to work done by Thon Taddeo. After arriving at the monastery, Thon Taddeo, by studying the Memorabilia, makes several major "discoveries", and asks the abbot to allow the Memorabilia to be removed to Texarkana. The Abbot Dom Paulo refuses, stating he can continue his research at the abbey. Before departing, the Thon comments that it could take decades to finish analyzing the Memorabilia.
Meanwhile, Hannegan makes an alliance with the kingdom of Laredo and the neighboring, relatively civilized city-states against the threat of attack from the nomadic warriors. Hannegan, however, is manipulating the regional politics to effectively neutralize all of his enemies, leaving him in control of the entire region. Monsignor Apollo, the papal nuncio to Hannegan's court, sends word to New Rome that Hannegan intends to attack the empire of Denver next, and that he intends to use the abbey as a base of operations from which to conduct the campaign. For his actions, Apollo is executed, and Hannegan initiates a church schism, declaring loyalty to the Pope to be punishable by death. The Church excommunicates Hannegan.
It is the year 3781, and mankind has nuclear energy and weapons again, as well as starships and extra-solar colonies. Two world superpowers, the Asian Coalition and the Atlantic Confederacy, have been embroiled in a cold war for 50 years. The Leibowitzan Order's mission of preserving the Memorabilia has expanded to the preservation of all knowledge.
Rumors that both sides are assembling nuclear weapons in space and that a nuclear weapon has been detonated increase public and international tensions. At the abbey, the current abbot, Dom Jethras Zerchi, recommends to New Rome that the Church reactivate the Quo Peregrinatur Grex Pastor Secum ("Whither Wanders the Flock, the Shepherd is with Them") contingency plans involving "certain vehicles" the Church has had since 3756. A "nuclear incident" occurs in the Asian Coalition city of Itu Wan: an underground nuclear explosion has destroyed the city, and the Atlantic Confederacy counters by firing a "warning shot" over the South Pacific.
New Rome tells Zerchi to proceed with Quo Peregrinatur and plan for departure within three days. He appoints Brother Joshua as mission leader, telling him that this is an emergency plan for perpetuating the Church on the colony planets in the event of a nuclear war on Earth. The Order's Memorabilia will also accompany the mission. That night the Atlantic Confederacy launches an assault against Asian Coalition space platforms. The Asian Coalition responds by using a nuclear weapon against the Confederacy capital city of Texarkana. A ten-day cease-fire is issued by the World Court. Brother Joshua and the space-trained monks and priests depart on a secret, chartered flight for New Rome, hoping to leave Earth on the starship before the cease-fire ends.
During the cease-fire, the abbey offers shelter to refugees fleeing the regions affected by fallout, which results in a battle of wills over euthanasia between the abbot and a doctor from a government emergency response camp. The war resumes and a nuclear explosion occurs near the abbey. Abbot Zerchi tries to flee to safety, bringing with him the abbey's ciborium containing consecrated hosts, but it is too late. He is trapped by the falling walls of the abbey and finds himself lying under tons of rock and bones as the abbey's ancient crypts disgorge their contents. Among them is a skull with an arrow's shaft protruding from its forehead (presumably that of Brother Francis Gerard from the first section of the book).
As he lies dying under the abbey's rubble, Zerchi is startled to encounter Mrs Grales/Rachel, a bicephalous tomato peddler and mutant. However, Mrs. Grales has been rendered unconscious by the explosion, and may be dying herself. As Zerchi tries to conditionally baptize Rachel, she refuses, and instead takes the ciborium and administers the Eucharist to him. It is implied that she is, like the Virgin Mary, Eve and Jesus, exempt from original sin, and may even be the Second Coming of Christ to begin a new cycle on Earth. Zerchi soon dies, having witnessed an apparent miracle.
After the Abbot's death, the scene flashes to Joshua and the Quo Peregrinatur crew launching as the nuclear explosions begin. Joshua, the last crew member to board the starship, knocks the dirt from his sandals (a reference to Matthew 10:14, "If anyone will not welcome you or listen to your words, leave that home or town and shake the dust off your feet"), murmuring "Sic transit mundus" ("Thus passes the world", a play on the phase sic transit gloria mundi, "thus passes the glory of the world"). As a coda, there is a final vignette depicting the ecological aspects of the war: seabirds and fish succumb to the poisonous fallout, and a shark evades death only through moving to particularly deep water, where, it is noted, the shark was "very hungry that season".
Scholars and critics have noted the theme of cyclic history or recurrence in Miller's works, epitomized in A Canticle for Leibowitz. David Seed, in discussing the treatment of nuclear holocaust in science fiction in his book American Science Fiction and the Cold War: Literature and Film (1992), states, "it was left to Walter M. Miller's A Canticle for Leibowitz to show recurrence taking place in a narrative spanning centuries." David N. Samuelson, whose 1969 doctoral dissertation on Canticle is considered the "best overall discussion of the book", calls the "cyclical theme of technological progress and regress ... the foundation-stone on which A Canticle for Leibowitz is built."
A Canticle for Leibowitz's circular structure – and the cyclical history it presents – support a number of thematic and structural elements which unify its three sections. Although the novel's events take place in a fictional future, the three parts allegorically represent crucial phases of Western history. The first section, "Fiat Homo", depicts a Church preserving civilization, a counterpart to the "Age of Faith" after the Fall of Rome. The action of the second part, "Fiat Lux", focuses on a renaissance of "secular learning", echoing the "divergences of Church and State and of science and faith". "Fiat Voluntas Tua", the final part, is the analog of contemporary civilization, with its "technological marvels, its obsessions with material, worldly power, and its accelerating neglect of faith and the spirit."
In her analysis of Miller's fiction, Rose Secrest connects this theme directly to one of Miller's earlier short fiction works, quoting a passage from "The Ties that Bind", published in the May 1954 edition of If magazine: "All societies go through three phases.... First there is the struggle to integrate in a hostile environment. Then, after integration, comes an explosive expansion of the culture-conquest.... Then a withering of the mother culture, and the rebellious rise of young cultures."
The third part, "Fiat Voluntas Tua", includes a debate between future Church and state stances on abortion and euthanasia, a thematic issue representative of the larger conflict between Church and state. Literary critic Edward Ducharme claimed that "Miller's narrative continually returns to the conflicts between the scientist's search for truth and the state's power."
Initial response to the novel was mixed, but it drew responses from newspapers and magazines normally inattentive to science fiction. A Canticle for Leibowitz was reviewed in such notable publications as Time, The New Yorker, the New York Times Book Review, and The Spectator. While The New Yorker was negative – calling Miller a "dull, ashy writer guilty of heavy-weight irony" – The Spectator's was mixed. Also unimpressed, Time said, "Miller proves himself chillingly effective at communicating a kind of post-human lunar landscape of disaster", but dubbed it intellectually lightweight. The New York Times Book Review, however, was solid in its praise – Martin Levin hailed A Canticle for Leibowitz as an "ingenious fantasy". The Chicago Tribune gave the book unusual exposure outside the genre in a front page review in the Chicago Tribune Magazine of Books, reviewer Edmund Fuller calling the book "an extraordinary novel". Genre reviewer Floyd C. Gale praised its "many passages of remarkable power". A decade later, Time re-characterized its opinion of the book, calling it "an extraordinary novel even by literary standards, [which] has flourished by word of mouth for a dozen years".
Sales of the hardcover publication were significant enough to justify two additional reprints of the book within the first year, and the novel was recognized with a Hugo Award by science fiction and fantasy fans as the best science fiction novel of 1960.
In the years since, praise for the work has been consistently high. It is considered a "science-fiction classic ... [and] is arguably the best novel written about nuclear apocalypse, surpassing more popularly known books like On the Beach". A Canticle for Leibowitz has also generated a significant body of literary criticism, including numerous literature journal articles, books and college courses. Acknowledging its serialization roots, literary critic David N. Samuelson writes that A Canticle for Leibowitz "may be the one universally acknowledged literary masterpiece to emerge from magazine SF." Fellow critic David Cowart places the novel in the realm of works by Evelyn Waugh, Graham Greene, and Walker Percy, in 1975 stating it "stands for many readers as the best novel ever written in the genre". Percy, a National Book Award recipient, declared Canticle "a mystery: it's as if everything came together by some felicitous chance, then fell apart into normal negative entropy. I'm as mystified as ever and hold Canticle in even higher esteem." Scholars and critics have explored the many themes encompassed in the novel, frequently focusing on its motifs of religion, recurrence, and church versus state.
A 15-part full-cast abridged serial of the novel was adapted for radio by John Reeves and broadcast in 1981 by National Public Radio (NPR). Directed by Karl Schmidt, it was produced by Karl Schmidt and Marv Nonn. Carol Cowan narrated the production.
In 1993 the BBC broadcast a 90-minute dramatisation of the first two parts, "Fiat Homo" and "Fiat Lux", with Andrew Price as Brother Francis and Michael McKenzie as Dom Paulo. The adaptation was by Donald Campbell and it was directed by Hamish Wilson.
A 2012 adaptation of "Fiat Homo, Part One of A Canticle For Leibowitz" read by Nigel Lindsay, abridged by Nick McCarty and produced by Philippa Geering for BBC Radio 4 Extra, was broadcast in five 30 minute parts.
Toward the end of his life, Miller wrote another installment of the Abbey of Saint Leibowitz saga, Saint Leibowitz and the Wild Horse Woman. A full-length novel (455 pages) significantly longer than its predecessor, it is set in AD 3254, eighty years after the events of "Fiat Lux" but several centuries before "Fiat Voluntas Tua". Suffering from writer's block and fearful the new work would go unfinished, Miller arranged with author Terry Bisson to complete it. According to Bisson, all he did was go in and tie up the loose ends Miller had left. The novel tells the story of Brother Blacktooth St. George of the Leibowitzan abbey who, unlike Brother Francis, wants to be released from his holy vows and leave the abbey. In addition to recounting his travels as Cardinal Brownpony's personal secretary, the book describes the political situation in the 33rd century as Church and empire (Texark) vie for power. Miller died before the novel's publication.
Saint Leibowitz and the Wild Horse Woman has been called "Walter Miller's other novel". Reviewer Steven H. Silver points out that this "is not to say that Saint Leibowitz and the Wild Horse Woman does not deserve to be read. It is a fantastic novel, only suffering in comparison to Miller's earlier work."