The Prince by Macchiavelli
The Republic by Plato
Hamlet by Shakespeare
Anything by Ambrose Bierce
The Crucible by Arthur Miller
All my Sons by Arthur Miller
Travels with Charley by Steinbeck
1984 by Orwell
The Grapes of Wrath by Steinbeck
The Picture of Dorian Gray by Oscar wilde
The Wind in the Willows by Kenneth Grahame
The Ballad of Reading Gaol by Oscar Wilde
The Count of Monte Cristo by Alexandre Dumas
Cyrano de Bergerac by Edmond Rostand
The entire bibliography of Emile Zola
Shantaram by Roberts
Anything by Guy de Maupassant
Animal Farm by Orwell
Down and Out in Paris by Orwell
Of Human Bondage by Somerset Maugham
The Painted Veil by Somerset Maugham
Farewell to Arms by Hemingway
The Old Man and the Sea by Hemingway
The Plague by Camus
The Stranger by Camus
Of Mice and Men by Steinbeck
Anything by PG Wodehouse
Anything by Chekov
The Idiot by Dostoyevsky
Pretty much anything by Tolstoy
Les Miserables by Victor Hugo
Crime Passionel by JP Sartre
Vanity Fair by William Thackeray
The notebooks of Leonardo da Vinci
The Illiad and the Odyssey by Homer
Aesop's Fables
Cicero's speeches
Julius Caesar's "Gallic wars"
Metamorphosis by Franz Kafka
The Fly by Kafka
Pretty much anything by Jules Verne
Rob Roy by Walter Scot
South by Ernest Shackelton
Moomins series by Tove Jansen
Pretty much all of Mark Twain
To begin with...

all these I cannot imagine not having read. I would have missed so much.