This list shows a few works of music, literature, and film that, as far as I can tell, were first published in the years shown.  The "Subverted Public Domain" begins with the year 1923.  Works published in that year would already be in the public domain but were saved by the Sonny Bono Copyright Term Extension Act of 1998. Any United States work published before 1964 lost its copyright in the 28th year after publication unless the copyright was formally renewed at the Copyright Office.   (Congress made renewal automatic for works published after 1963, so most of those works are, and for a very long time will be, under copyright.)  To check on the copyright status of works from the 1923-63 era, it is therefore necessary to determine whether the copyright was renewed.  See How to Determine Whether a Work is in the Public Domain, and links contained there, for more details.

1919 (entered public domain Jan. 1, 1995)

 Music

  Swanee by George Gershwin and Irving Caesar
  A Pretty Girl Is like a Melody by Irving Berlin

 Books and Poems

1920-1921 (entered public domain Jan. 1, 1996 or 1997)

 Music

  AfterYou've Gone  by Henry Creamer and Turner Layton
  Till the Clouds Roll By by Jerome Kern and P.G. Wodehouse
  Over There by George M. Cohan
  Till We Meet Again by Richard Whiting and Raymond Egan

 Books and Poems

   F. Scott Fitzgerald:  This Side of Paradise
   D.H. Lawrence:  Women in Love 
   Edith Wharton:  The Age of Innocence

1922 (entered public domain Jan. 1, 1998)

 Music

  Look for the Silver Lining by Jerome Kern and Bud DeSylva
  Avalon by Al Jolson, Bud DeSylva, and Vincent Rose

 Books and Poems

  T.S. Eliot:  The Waste Land 
   Marcel Proust:  Swann's Way (first English translation)
  James Joyce:  Ulysses 

 Films

  Blood and Sand with Rudolph Valentino

1923 (should have been public domain Jan. 1, 1999)

 Books and Poems

  Willa Sibert Cather:  A Lost Lady, Nebraska, and The End Of The First Cycle
  Joseph Conrad:  Christmas Day at Sea and Outside Literature
  Arthur Conan Doyle: The Adventure Of The Creeping Man and The Adventure Of The Sussex Vampire 
  F. Scott Fitzgerald:  Hot and Cold Blood and Invasion of the Sanctuary
  James Frazer: The Golden Bough
  Zane Grey:  Code of the West, Steelhead, Tappan's Burro,The Vanishing American, and Down into the Desert
  Ben Hecht:  Fingers at the Window
  Rudyard Kipling:  Independence and London Stone
  Ring Lardner:   Blue Beard, Why Authors?, Cinderella, The Dames, What I Ought To Of Learnt In High School, and Bringing Up Children
  Amy Lowell:  Cut Shadow, Fact, Green Shadows, Rosebud Wall Paper, and Dissonance
  W. Somerset Maugham:  Bewitched, German Harry, Mayhew, and The Force of Circumstances 
  Edna St Vincent Millay:  The Harp-Weaver, And Other Poems, Memory of Cape Code, To the Liberty Bell, and The Concert 
  Wallace Stevens:  Harmonium 
  Booth Tarkington:  The Coincidence, The Power of the Press, and The Midlander 
  P.G. Wodehouse: Jeeves, First Aid for Dora Heart of a Goof, Leave It to Psmith, Magic Plus Fours, No Wedding Bells for Him,The Return Of Battling Billson, Rollo Podmarsh Comes To, Ukridge Rounds A Nasty Corner, and Chester Forgets Himself 
  Virginia Woolf:  Jacob's Room
  William Butler Yeats:  Meditations In Time Of Civil War

 Plays

  Noel Coward:  The Young Idea 
  Luigi Pirandello (trans Arthur Livingston):  Each In His Own Way, And Two Other Plays

 Films

  Safety Last by Harold Lloyd
  Little Church Around the Corner

Music

You're The Cream In My Coffee, words and music by B.G. De Sylva, Lew Brown and Ray Henderson
Who's Sorry Now?, words and music by Bert Kalmar, Ted Snyder, And Harry Ruby
I Cried For You (Now It's Your Turn To Cry Over Me), by Arthur Freed, Gus Arnheim and Abe Lyman
Chansonette, music by Rudolf Friml, lyrics by Irving Caesar, Dailey Paskman, and Sigmund Spaeth
Yes! We Have No Bananas, by Frank Silver and Irving Cohn

1924 (should have been public domain Jan. 1, 2000)

 Films

  Sherlock, Jr.
  Dixie

Music

When My Sugar Walks Down The Street (All The Little Birdies Go Tweet Tweet Tweet), words and music by Gene Austin, Jimmy McHugh and Irving Mills
It Had To Be You, lyric by Gus Kahn, music by Isham Jones
Fascinating Rhythm; The Man I Love, by George & Ira Gershwin
Sleepy Time Gal, lyric by Jos. R. Alden and Raymond B. Egan
Amapola
Everybody Loves My Baby, words and music by Jack Palmer and Spencer Willson
All Alone; They Call It Dancing; Lazy; What'll I Do?, words and music by Irving Berlin
I'll See You In My Dreams, lyrics by Gus Kahn, music by Isham Jones
Moonlight And Roses, by Edwin H. Lemare, Ben Black and Neil Moret
Memory Lane, lyrics by B.G. De Sylva, music by Larry Spier and Con Conrad
When Day Is Done, lyrics by B.G. De Sylva, music by Dr. Robert Katscher
Rose Marie; Indian Love Call; Totem Tom Tom, from the musical play and film Rose Marie, music by Rudolph Friml and Herbert Stothart, book and lyrics by Otto Harbach and Oscar Hammerstein 2nd
Golden Days; Just We Too; Deep In My Heart, Dear (Sorry, Dad), from The Student Prince, by Sigmund Romberg

1925 (should have been public domain Jan. 1, 2001)

 Films

  Felix the Cat (the character goes into the PD together with the first film in which he appears)

Music

I'm Tired of Everything But You, words and music by Isham Jones
Manhattan, lyrics by Lorenz Hart, music by Richard Rodgers
Angry, lyrics and arrangement by Dudley Mecum, Henry and Merritt Brunies, and Jules Cassard
Remember; Always; Florida By The Sea; Paddlin' Madelin' Home, words and music by Irving Berlin
Dinah, words by Sam M. Lewis & Joe Young, music by Harry Akst
Side By Side, words and music by Harry Woods
Cecilia (Does Your Mother Know You're Out?), words by Herman Ruby, music by Dave Dreyer
Jalousie, music by Jacob Gade, words by Vera Bloom
Five Foot Two, Eyes Of Blue, lyrics by Sam M. Lewis and Joe Young, music by Ray Henderson
Valencia (A Song Of Spain), words by Lucien Boyer and Jacques-Charles, music by Jose Padilla, American version by Clifford Grey

1926 (should have been public domain Jan. 1, 2002)

 Music

  Irving Berlin:  Blue Skies
  Rodgers & Hart:   The Blue Room, from The Girl Friend 
  Sigmund Romberg:  The Desert Song and The Student Prince 
  Harry Woods:  When the Red, Red Robin Comes Bob, Bob Bobbin' Along

1927 (should have been public domain Jan. 1, 2003)

 Music

  Oscar Hammerstein II and Jerome Kern:  Ol' Man River and Showboat

 Films

  Wins
  Sunrise

1928 (should have been public domain Jan. 1, 2004)

 Characters

  Mickey Mouse