Short answers, pulled from the story.
William Shakespeare wrote Henry IV, Part 1 no later than the year 1597. The earliest recorded performance took place on the afternoon of the 6th of March 1600 before the Flemish Ambassador at court.
The play follows three distinct groups including King Henry IV with his council, rebel lords led by Thomas Percy Earl of Worcester and Harry Percy nicknamed Hotspur, and Prince Hal with comic companions like Falstaff Poins Bardolph and Peto. These groups converge at the climax during the Battle of Shrewsbury after initially interacting only indirectly.
Political pressure from the Cobham family forced the change since they were powerful nobles who withdrew official protection from Shakespeare's acting company after becoming Lord Chamberlain in 1596. Historical records indicate the original character was based on John Oldcastle a famous proto-Protestant martyr with living descendants in England.
Falstaff dismisses honor as an abstract concept lacking tangible benefits or practical value concluding that it is merely air and offers nothing to the living. This pragmatic viewpoint contrasts sharply with romanticized notions of martial society valuing noble pursuits worth dying for.
At its first publication in 1597 or 1598 the play was titled The History of Henrie the Fourth and advertised only Henry Percy and comic Sir John Falstaff without mentioning Prince Hal. It was not until the twentieth century that readers began seeing central interest in Hal's coming-of-age story while popular actors previously favored playing Hotspur.