Miguel de Cervantes wrote Don Quixote in 1605. It is considered the first modern novel. Some call it the greatest novel of all time. If you use the term, don’t go chasing windmills, you are referring to this book.
It tells a story about hope used as weapons against a morally deteriorating, cynical world. Main character Don Quixote is a nobleman who spends his time reading books of romance and chivalry until he enters a world where he believes it to be true. He takes up an imaginary quest, fights battles against fancied enemies, even a windmill that he imagines to be a dragon.
He is opposed by family and a professional class that resist any opposition to their solid and unyielding reality. To them, there is no room for free thought, even by a harmless, kindly old man.
It was filled with social commentary of current events, which is how many novels were written at the time.
Is Don Quixote an enlightened dreamer or a madman who has no place in his environment? Readers can draw their own conclusions. But it is clear that Cervantes is solidly behind his knight errant who was obsolete even in 1605.