Gallico was born in New York City. His father was an Italian, and his mother came from Austria; they had emigrated to New York in 1895. Gallico graduated from Columbia University in 1919 and first achieved notability in the 1920s as a sportswriter, sports columnist, and sports editor of the New York Daily News. His career was launched by an interview with boxer Jack Dempsey in which he asked Dempsey to spar with him, and described how it felt to be knocked out by the heavyweight champion. He followed up with accounts of catching Dizzy Dean's fastball and golfing with Bobby Jones. He became a national celebrity and one of the highest-paid sportswriters in America. He founded the Golden Gloves amateur boxing competition. His 1942 book, Lou Gehrig: Pride of the Yankees was adapted into a classic sports movie.

In the late 1930s, he abandoned sports writing for fiction, first writing an essay about this decision entitled "Farewell to Sport" (published in an anthology of his sports writing, also titled Farewell to Sport (1938)), and became an extremely successful writer of short stories for magazines, many appearing in the then-premier fiction outlet, The Saturday Evening Post. Many of his novels, including The Snow Goose, are expanded versions of his magazine stories.

Gallico once told New York Magazine "I'm a rotten novelist. I'm not even literary. I just like to tell stories and all my books tell stories.... If I had lived 2,000 years ago I'd be going around to caves, and I'd say, 'Can I come in? I'm hungry. I'd like some supper. In exchange, I'll tell you a story. Once upon a time there were two apes.' And I'd tell them a story about two cavemen."

The Snow Goose was published in 1941 in The Saturday Evening Post and won the O. Henry Award for short stories in 1941. Critic Robert van Gelder called it "perhaps the most sentimental story that ever has achieved the dignity of a Borzoi [prestige imprint of publisher Knopf] imprint. It is a timeless legend that makes use of every timeless appeal that could be crowded into it." A public library puts it on a list of "tearjerkers." Gallico made no apologies, saying that in the contest between sentiment and "slime", "sentiment remains so far out in front, as it always has and always will among ordinary humans that the calamity-howlers and porn merchants have to increase the decibels of their lamentations, the hideousness of their violence and the mountainous piles of their filth to keep in the race at all."

His short story, "The Man Who Hated People" was reworked into his book Love of Seven Dolls, which was adapted into the 1953 Oscar-winning motion picture Lili. It was later staged as a musical, Carnival! The versions differ significantly, but all center around the story of a relationship between a puppeteer and a painfully shy and confused young woman. Overhearing her talking to herself about her emotional distress, he speaks to her through his puppets and she develops a relationship with him through them. He has severe emotional problems of his own and bitterly mistreats her.

His novel, Mrs. 'Arris Goes to Paris, published in 1958, was a bestseller, and he wrote three more books about the lovable charlady, 'Mrs. 'Arris'.

The Silent Miaow (1964) purports to be a guide written by a cat, "translated from the feline", on how to obtain, captivate, and dominate a human family. Illustrated with photographs by Suzanne Szasz, it is considered a classic by cat lovers. Other Gallico cat books include Jennie (1950) (American title The Abandoned), Thomasina: The Cat Who Thought She Was God (1957), filmed in 1964 by the Walt Disney Studios as The Three Lives of Thomasina (which was very popular in the former USSR in the early 1990s, inspiring the Russian remake Bezumnaya Lori), and Honorable Cat (1972), a book of poetry and essays about cats.

Gallico's 1969 book The Poseidon Adventure, about a group of passengers attempting to escape from a capsized ocean liner, attracted little attention at the time. The New York Times gave it a one-paragraph review, noting that "Mr. Gallico collects a Grand Hotel [a reference to the 1930 Vicki Baum novel] full of shipboard dossiers. These interlocking histories may be damp with sentimentality as well as brine—but the author's skill as a storyteller invests them with enough suspense to last the desperate journey." In contrast, Irwin Allen's motion picture adaptation of Gallico's book was instantly recognized as a great movie of its kind. In his article "What makes 'Poseidon' Fun?", reviewer Vincent Canby coined the term "ark movie" for the genre including Airport, The High and the Mighty, A Night to Remember, and Titanic (the 1953 movie). He wrote that "the Poseidon Adventure puts the Ark Movie back where God intended it to be, in the water. Not flying around in the air on one engine or with a hole in its side." The movie was enormously successful, spawned a whole decade of disaster films, and is a cult classic today.

In his New York Times obituary, Molly Ivins said that "to say that Mr. Gallico was prolific hardly begins to describe his output." He wrote 41 books and numerous short stories, twenty theatrical movies, twelve TV movies, and had a TV series based on his Hiram Holliday short stories.

Gallico is a self-described "storyteller." Many of his stories are told in the apparently artless style of a folk tale or legend. Like other "storyteller" writers, the charm and power lie in something about the cumulative effect of plainly told detail after plainly told detail. A summary outline of a Gallico story may sound uninteresting, even bordering on ludicrous; an individual quotation broken out of its context falls flat; their essence exists only in their entirety.

For example, consider Molly Ivins' summary of The Snow Goose:

The Snow Goose is a tale about a disabled painter living in a lonely lighthouse on the coast of the county of Essex in England. One day a girl brings to him a wounded snow goose, which he nurses back to health. The goose returns each year, as does the girl, and a romance develops between the girl and the artist. But the artist is killed rescuing soldiers after the evacuation of Dunkirk, while the snow goose flies overhead.

Andrea Park, in a review of Love of Seven Dolls, notes that Gallico's work has power only as a textural whole. "It is difficult to describe and impossible to pinpoint the tenuous, even nebulous word magic that successfully carries a reader into the world of fantasy and make-believe. It is perhaps delineated as a quality, a kind of fragile atmosphere that, once established, cannot be broken. Mr. Gallico creates this atmosphere when he writes the sequences with Mouche and the puppets."

Beginning writers are often advised to show rather than to describe. One of the mysteries of Gallico's style is its effectiveness despite his constant violation of this rule. When he wants us to know that a Peyrot is cynical, he says "Wholly cynical, he had no regard or respect for man, woman, child, or God." When he wants us to know that Mouche is innocent, he tells us of her "innocence and primitive mind." When he wants us to know that Rhayader has a warm heart in his crippled body, he says "His body was warped, but his heart was filled with love for wild and hunted things." Much of Gallico's stories are told as a string of assertions and generalities, illuminated only by touches of the particular and specific.

Gallico sometimes sets the scene by describing his stories as legends. Within the text of The Snow Goose he says that "this story... has been garnered from many sources and from many people. Some of it comes in the form of fragments from men who looked upon strange and violent scenes." Later he writes "Now the story becomes fragmentary, and one of these fragments is in the words of the men on leave who told it in the public room of the Crown and Arrow, an East Chapel pub." Given this presentation, it is hardly surprising that it has been taken to be a retelling of an actual legend; Gallico writes that "the person and character of the painter are wholly fictional as is the story itself, although I am told that in some quarters the snow goose appearing over Dunkirk has been accepted as legend and I have been compelled to reply to many correspondents that it was sheer invention."

Martin Levin wrote that "Mr. Gallico has long had a way with the quasi-human—puppets (Love of Seven Dolls), cows (Ludmila,) geese (The Snow Goose)" as well as no fewer than five books about cats.

Often, Gallico's point of view implies that the nonhuman character in some way really possesses a human spirit, or a portion of a human spirit. In The Love of Seven Dolls, the puppeteer's relation to his puppets suggests at least a resemblance to dissociative identity disorder or "multiple personality" disorder, a disorder which was well-known to the lay public in the 1950s. It is significant that Gallico never even hints at such a thing. He notes that the puppeteer's "primitive" Senegalese assistant "looked upon the puppets 'as living, breathing creatures.'" and that "the belief in the separate existence of these little people was even more basic with Mouche for it was a necessity to her and a refuge from the storms of life with which she had been unable to cope." One could go so far as to say that he leaves it deliberately ambiguous whether the relation between the puppeteer and his puppets is purely natural or whether there could be at least a trace of the supernatural in it. This ambiguity is hinted at in the close of the movie adaptation, Lili. Although the puppeteer Paul's hands are engaged in embracing Lili, the four puppets somehow peek around the puppet stage proscenium to smile their happy approval (and applaud), apparently under their own power.

The treatment contrasts with the 1954 Danny Kaye vehicle, Knock on Wood, which turns on the similar theme of a ventriloquist who can express his true self only through his dummy. This movie not only hints at a psychiatric undertone, it revels in it; Kaye's character's love interest is a "lady psychiatrist" (in the phrase used by a contemporary reviewer). The pop-psychiatric point of view was prevalent during the late 1940s and 1950s, the same period that brought us the psychoanalytic musical Lady in the Dark and the book The Three Faces of Eve. Gallico's distancing of his writing from this "modern" point of view and his use of the language of legend and fairy-tale seems deliberate, the literary equivalent of what painter Thomas Kinkade does today in his painting. However, some fans of Gallico and critics of Kinkade would argue that Gallico's literary art is more comparable to the paintings of nineteenth century Russian painter Victor Vasnetsov, as Vastenov's works are more firmly rooted in genuine sentimentality and folk tradition as opposed to Kinkade's work which is often criticized as "cheezy," "schmaltz," and "cookie-cutter pop-art."

in 2000 J. K. Rowling declared that Gallico's 1968 Manxmouse was one of her favorite childhood books. In fact the boggarts appearing in Rowling's Harry Potter books closely resemble Manxmouse's "clutterbumph" which takes the form of whatever the viewer fears the most. Manxmouse was illustrated by Anne and Janet Grahame-Johnstone who also illustrated The Hundred and One Dalmatians by Dodie Smith. The Japanese animation studio Nippon Animation adapted this tale into a feature-length anime film in 1979, directed by Hiroshi Saito. The anime, titled Tondemo Nezumi Daikatsuyaku: Manxmouse (Manxmouse's Great Activity) in Japanese, was dubbed into English in the 1980s, broadcast on Nickelodeon, and released on video by Celebrity Home Entertainment.

A television series, The Adventures of Hiram Holliday (starring Wally Cox) was adapted from a series of Gallico's stories about a newspaper proofreader who had many adventures dealing with Nazis and spies in Europe on the eve of World War II.

In Fredric Brown's science-fiction novel What Mad Universe a magazine editor from our own world is accidentally sent to a parallel Earth significantly different from ours; in this parallel world, the editor reads a biography written of a fictional public figure central to the novel's narrative supposedly written by Paul Gallico.

In 1975, the British progressive rock band Camel released an album of work based on Gallico's The Snow Goose. Although the author was initially opposed to the album's release, legal action was evaded on the condition that the band used the words Music Inspired by The Snow Goose on the album's cover.

Bibliography

Books

• Farewell to Sport (1938) sport
• The Adventures of Hiram Holliday (1939) (US: Adventures of Hiram Holliday) light
• The Secret Front (1940)
• The Snow Goose (1941) light-tragedy
• Golf is a Friendly Game (1942) sport
• Lou Gehrig: Pride of the Yankees (1942) sport
• Selected Stories of Paul Gallico (1944)
• The Lonely (1947) light
• Confessions of a Story Writer (1948)
• Jennie (1950) (US: The Abandoned) light-tragedy
• The Small Miracle (1951) light
• Trial by Terror (1952)
• Snowflake (1952)
• The Foolish Immortals (1953) adventure
• Love of Seven Dolls (1954) light-tragedy
• Ludmila (1955) light
• Thomasina (1957) light-tragedy
• Flowers for Mrs. Harris (1958) (US: Mrs. 'Arris goes to Paris) light
• The Steadfast Man (1958)
• Too Many Ghosts (1959) [follow-on to Hand of Mary Constable]
• The Hurricane Story (1960)
• Mrs. Harris goes to New York (1960) (US: Mrs. 'Arris goes to New York) light
• Confessions of a Story Teller (1961) US: Further Confessions of a Story Writer)
• Scruffy (1962) light
• Coronation (1962) light
• Love, Let Me Not Hunger (1963) light-tragedy
• The Day the Guinea-Pig Talked (1963) children
• Three Stories (1964) (US: Three Legends)
• The Hand of Mary Constable (1964)
• The Silent Miaow (1964)
• The Day Jean-Pierre was Pignapped (1964) children
• Mrs. Harris, M.P. (1965) (US: Mrs. 'Arris goes to Parliament) light
• The Day Jean-Pierre Went Round the World (1965) children
• The Golden People (1965) sport
• The Man who was Magic (1966) light
• The Story of Silent Night (1967)
• The Revealing Eye (1967)
• Gallico Magic (1967)
• Manxmouse (1968) light
• The Poseidon Adventure (1969)
• The Day Jean-Pierre Joined the Circus (1969) light
• Matilda (1970) light
• The Zoo Gang (1971) light
• Honourable Cat (1972) (US: Honorable Cat)
• The Boy who invented the Bubble Gun (1974) light
• Mrs. Harris goes to Moscow (1974) (US: Mrs. 'Arris goes to Moscow) light
• Miracle in the Wilderness (1975)
• Beyond the Poseidon Adventure (1978)
• The House that Wouldn't Go Away (1979) light
• The Best of Paul Gallico (1988)

Select list of adaptations

Film

• 1953, Lili, based on The Love of Seven Dolls
• 1964, The Three Lives of Thomasina, based on Thomasina: The Cat Who Thought She Was God (1957)
• The Snow Goose
• 1972, The Poseidon Adventure
• 1972, Honorable Cat
• Lou Gehrig: Pride of the Yankees
• 1991, Bezumnaya Lori , based on Thomasina

Television

• 1974, The Zoo Gang
• The Adventures of Hiram Holliday series
• Tondemo Nezumi Daikatsuyaku: Manxmouse (Manxmouse's Great Activity)

Stage musical

• Carnival!, based on The Love of Seven Dolls

Music

• 1975, Music inspired by the Snow Goose, album by the British progressive rock band Camel, based on The Snow Goose