Short answers, pulled from the story.
Henry IV, Part 1 was almost certainly in performance by 1597. The earliest recorded performance took place on the afternoon of the 6th of March 1600, when the play was acted at court before the Flemish Ambassador. It was entered into the Register of the Stationers Company on the 25th of February 1598 and first printed in quarto that same year by stationer Andrew Wise.
Sir John Falstaff is a cowardly, drunken, quick-witted knight and Prince Hal's closest companion in the play. He is significant both dramatically and historically: the character was originally named Oldcastle, based on a Protestant martyr with powerful living descendants, and had to be renamed after political pressure. The character's popularity drove multiple printings of the play and is believed by some scholars to have prompted Shakespeare to expand a single Henry IV play into two parts.
When Henry IV, Part 1 first appeared on stage in 1597, the comic knight was named Oldcastle, based on John Oldcastle, a Protestant martyr with powerful living descendants including William Brooke, 10th Baron Cobham, and his son Henry Brooke, 11th Baron Cobham. Political pressure forced Shakespeare to rename the character Falstaff, after Sir John Fastolf, a historical figure with a reputation for cowardice at the Battle of Patay who died without descendants.
Falstaff's Catechism is a soliloquy delivered in Act 5, Scene 1, in which Falstaff questions whether honour can heal wounds, restore a limb, or provide any tangible benefit, concluding that honour is merely "air" and "a mere scutcheon." Professor Clifford Davidson identified a parallel with Philippe de Mornay's 1582 treatise De la verité de la religion chrestienne, which uses similar language and a catechetical structure to reduce honour to wind.
The Dering Manuscript is the earliest surviving manuscript of any Shakespeare play. Scholars believe it was prepared around 1623 by Edward Dering (1598-1644) of Surrenden Manor, Pluckley, Kent, where the manuscript was discovered. It combines Henry IV, Part 1 and Part 2 into a single text and is held at the Folger Shakespeare Library in Washington, D.C.
Notable adaptations include Orson Welles's 1965 film Chimes at Midnight, which combined both Henry IV plays with material from other Shakespeare works, and three BBC television productions in 1960, 1979, and 2012. The 2012 Hollow Crown series starred Jeremy Irons, Tom Hiddleston, and Simon Russell Beale. Netflix released The King in 2019, directed by David Michôd and starring Timothée Chalamet. In spring 2024, Robert Icke's stage adaptation Player Kings, starring Ian McKellen as Falstaff, ran at the Noel Coward Theatre in London's West End.