prelude to

a prelude to (something)

An introductory event or action. The economic troubles of these companies were just a prelude to the global financial meltdown that would the following year. We regard these acts of aggression as a prelude to war. I'm so unbelievably tired today—I really hope this isn't a prelude to the flu or something.
See also: prelude, to
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

prelude to something

an act or event that comes before and signals another act or event. Her rudeness to her boss was a prelude to her resignation. The Munich Pact was a prelude to World War II.
See also: prelude, to
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in classic literature ?
Brilliant performance of prelude to the Judge's song in "Trial by Jury" by nervous Pianist.
Pianist, thereupon, starts prelude to the Admiral's song, and Harris, seizing what he considers to be a favourable opening in the music, begins.]
The Communists turn their attention chiefly to Germany, because that country is on the eve of a bourgeois revolution that is bound to be carried out under more advanced conditions of European civilisation, and with a much more developed proletariat, than that of England was in the seventeenth, and of France in the eighteenth century, and because the bourgeois revolution in Germany will be but the prelude to an immediately following proletarian revolution.
Do you not know that all this is but the prelude to the actual strain which we have to learn?
In a few minutes he lifted his head, looked at me, and struck the first notes--the prelude to the song.
To be called into notice in such a manner, to hear that it was but the prelude to something so infinitely worse, to be told that she must do what was so impossible as to act; and then to have the charge of obstinacy and ingratitude follow it, enforced with such a hint at the dependence of her situation, had been too distressing at the time to make the remembrance when she was alone much less so, especially with the superadded dread of what the morrow might produce in continuation of the subject.
Rosebud, June 17, 1876: Prelude to the Little Big Horn
A Prelude to The Shed takes over an empty lot near the High Line for two weeks of ever-shifting programming.
A review of Prelude to Prison: Student Perspectives on School Suspension by Marsha Weissman (Syracuse: Syracuse University Press, 2015.
Los Angeles, CA, August 28, 2014 --( Star Trek fans worldwide made their voices heard by donating over $650,000 on Kickstarter and through PayPal to finance the independent film Star Trek: Axanar (follow-up to the highly-successful - and Kickstarter-funded - short, Prelude to Axanar).
Summary: Jumblatt warned that the release of three Army officers arrested over the killing of a prominent anti-Bashar Assad preacher might be a prelude to the freeing of former MP Michel Samaha,
Prelude to Power, the first of four new volumes, will reportedly contain 75% unpublished material.
In a cut-to-the-chase collection of the great moments of ecstasy in Wagner's operas/music dramas SPM (with an augmented orchestra of some 80 musicians) churned through the Prelude to Act III of "Lohengrin," "Dawn and Siegfried's Rhine Journey," from the last of the "Ring" cycle, "Gotterdammerung" the Prize Song from "Meistersinger" (with tenor Alan Schneider), the Prelude and Love-Death from "Tristan" (with soprano Joanna Porackova), the "Ride of the Valkyries," and the memorable final scene of Act I of "Die Walkure" (with both Schneider and Porackova.)
is an involuted poem which is about its own genesis--a prelude to itself" (Abrams 79).
"Prelude to Glory: The Life and Times Of A Texas Ranger" follows Leroy Wiley, a young Texas ranger, serving in the rough years during the pre-civil war era.