Henry VI part 1 is one of William Shakespeare's History plays.

No, it is classified as a 'History'.

Henry VI Part 1

Actually, it is three of Shakespeare's plays, called Henry VI Part 1, Henry VI Part 2 and Henry VI Part 3. They have alternate titles: "The First Part of the Contention betwixt the Famous houses of York and Lancaster" is Part 2, and "The Whole Contention between the Famous houses Lancaster and York" is Part 3, and so is "The True Tragedy of Richard Duke of York" Part 1 is supposed to be the play referred to in Philip Henslowe's notebook as "Harey VI"

Apart from Talbot and his son, all of the noblemen in Henry VI Part 1 are portrayed as selfish and treacherous, and dangerous to the health of the country.