DRAMATIS PERSONAE
KING HENRY THE FOURTH – King of England
HENRY, PRINCE OF WALES – eldest son of Henry IV; nicknamed "Hal" or "Harry"
JOHN OF LANCASTER – represented in the play as the King's second son, although he was actually the third
EARL OF WESTMORLAND
SIR WALTER BLUNT
SIR JOHN FALSTAFF – a knight who befriends Prince Hal
POINS – also called Ned
BARDOLPH
PETO
With a massive 616 lines (nearly 50 more than his closest competitor,  Hal ), Falstaff dominates the play just as he seems to dominate the dinner table and the brothels of Eastcheap. Usually cited as one of Shakespeare’s most enduring comic creations and only rivalled by  Hamlet  in certain moods, Falstaff has delighted the groundlings of Elizabethan theaters and  Yale professors  alike with his loquacious wit and lust for life. 
 
 Eduard von Grützner: Falstaff mit großer Weinkanne und Becher (Falstaff with big wine jar and cup), via  Wikimedia Commons. 
 It’s commonly reckoned that the character’s name was originally “Sir John Oldcastle”, referring to a Protestant martyr executed in 1417– the first quarto of the play uses this name. There is a (loosely) historical  “Fastolf”  in  1 Henry VI , from where Shakespeare seems to have lifted the name. 
 David Scott Kastan (p. 138) offers the following further analysis of the name: 
 the name probably also points at the reality behind the braggart-warrior’s boasts and his  eventual rejection : i.e. fall staff (an perhaps with some glance at ‘shake-spear’). 
 
 The Arden Shakespeare: King Henry IV,  ed. David Scott Kastan (London: Thomson Learning, 2002) 
 Harold Bloom,  Hamlet: Poem Unlimited  (Edinburgh: Canongate Books, 2003)
Henry IV Part 1 Characters of the Play