Here is the line-by-line modern paraphrase of the monologue:

Original: Then, Bolingbroke, as low as to thy heart,
Modern: So then, Bolingbroke, straight to your very heart I say this —

Original: Through the false passage of thy throat, thou liest.
Modern: Every word that passes through your lying throat is a lie.

Original: Three parts of that receipt I had for Calais
Modern: Three quarters of the money I received for Calais —

Original: Disbursed I duly to his highness’ soldiers;
Modern: I paid out honestly to the King’s soldiers —

Original: The other part reserved I by consent,
Modern: The remaining portion I kept back with full agreement —

Original: For that my sovereign liege was in my debt
Modern: Because my lord and King actually owed me money —

Original: Upon remainder of a dear account,
Modern: As the remaining balance of a costly debt —

Original: Since last I went to France to fetch his queen:
Modern: Going back to when I last traveled to France to bring back his queen.

Original: Now swallow down that lie.
Modern: So choke on that lie.

Original: For Gloucester’s death,
Modern: As for the death of Gloucester —

Original: I slew him not; but to my own disgrace
Modern: I did not kill him, but to my own shame —

Original: Neglected my sworn duty in that case.
Modern: I failed to carry out the duty I had sworn to perform.

Original: For you, my noble Lord of Lancaster,
Modern: As for you, my noble Lord of Lancaster —

Original: The honourable father to my foe
Modern: The honorable father of my enemy —

Original: Once did I lay an ambush for your life,
Modern: I once set a trap to take your life —

Original: A trespass that doth vex my grieved soul
Modern: A wrongdoing that still deeply troubles my guilty conscience —

Original: But ere I last received the sacrament
Modern: But before I last took Holy Communion —

Original: I did confess it, and exactly begg’d
Modern: I confessed that sin completely, and earnestly begged for —

Original: Your grace’s pardon, and I hope I had it.
Modern: Your forgiveness, and I believe you granted it.

Original: This is my fault: as for the rest appeall’d,
Modern: That is the one fault I own. As for all the other charges made against me —

Original: It issues from the rancour of a villain,
Modern: They come straight from the bitter hatred of a villain —

Original: A recreant and most degenerate traitor
Modern: A cowardly and thoroughly corrupt traitor —

Original: Which in myself I boldly will defend;
Modern: All of which I will fearlessly defend against with my own body —

Original: And interchangeably hurl down my gage
Modern: And in return I throw down my glove as a challenge —

Original: Upon this overweening traitor’s foot,
Modern: At the feet of this arrogant traitor —

Original: To prove myself a loyal gentleman
Modern: To prove that I am a true and faithful nobleman —

Original: Even in the best blood chamber’d in his bosom.
Modern: Even if it means spilling the finest blood in his chest.

Original: In haste whereof, most heartily I pray
Modern: With urgent desire for this to happen, I most sincerely beg —

Original: Your highness to assign our trial day.
Modern: Your Majesty to set the date for our trial by combat.

Act I, Scene i of Richard II opens in the court of King Richard II of England, where the king presides over a formal hearing between two noblemen: Henry Bolingbroke, the Duke of Hereford and son of John of Gaunt, and Thomas Mowbray, the Duke of Norfolk. Bolingbroke appears before the king to make a series of grave accusations against Mowbray, charging him with treason, misappropriation of royal funds meant to pay the king’s soldiers, and most seriously, the murder of Thomas of Woodstock, the Duke of Gloucester. Mowbray vigorously denies all of the charges brought against him, acknowledging only that he had once plotted against John of Gaunt, though he claims to have since sought and received the elder duke’s forgiveness. Both men exchange heated words and escalating insults, with each throwing down his gage — a glove — as a formal challenge to trial by combat.

King Richard II attempts on multiple occasions to bring peace between the two men, urging them to set aside their quarrel and appealing to both their loyalty to the crown and their bonds of kinship and fellowship. However, neither Bolingbroke nor Mowbray is willing to back down or withdraw his challenge, with both men insisting that their honor demands satisfaction through combat. Bolingbroke refuses to be reconciled with Mowbray regardless of the king’s wishes, and Mowbray equally holds firm. Finding himself unable to resolve the dispute through diplomacy, King Richard ultimately agrees to allow the matter to be settled through a formal trial by combat, with the date to be set at a later time.

Richard II opens with King Richard presiding over a dispute between Henry Bolingbroke (John of Gaunt’s son) and Thomas Mowbray, Duke of Norfolk. Both men accuse each other of treason, and when Richard cannot reconcile them, he arranges a trial by combat. However, just as the combat is about to begin, Richard stops the fight and banishes both men from England - Mowbray for life and Bolingbroke for six years, later reduced to four.

When John of Gaunt falls ill and dies, Richard seizes his lands and wealth to fund his wars in Ireland, effectively disinheriting Bolingbroke. This act alienates the nobility, who fear their own inheritances are now at risk. While Richard departs for his Irish campaign, Bolingbroke returns from exile with an army, ostensibly to reclaim his rightful inheritance. He quickly gains support from discontented nobles, including the Duke of York, who was left as regent in Richard’s absence.

Richard returns from Ireland to find his support has collapsed and his army has dispersed. After a series of encounters, including a pivotal scene at Flint Castle where Richard realizes his situation is hopeless, he agrees to abdicate. In a formal ceremony at Westminster, Richard hands over his crown to Bolingbroke, who becomes King Henry IV. Richard is imprisoned in Pomfret Castle, where he is eventually murdered by Sir Pierce Exton, who believes he is carrying out Henry’s wishes. The play ends with Henry expressing regret over Richard’s death and vowing to journey to the Holy Land to atone for his indirect role in the former king’s murder.