My Lord John is an unfinished historical fiction novel by the British author Georgette Heyer, published posthumously in 1975 after her death the previous year.

It traces the early lives of the "young lordings" – Harry, Thomas, John, and Humfrey – all sons of the future Lancastrian king Henry IV of England.

She felt that John, now largely unknown today, was ideal because he was a "great man" who lived during the entirety of her selected time period and was the most trusted brother of Henry V. However, Heyer failed to complete the trilogy, finding herself distracted with the writing of her popular Regency novels to please her fans and offset her tax liabilities.

Upon its publication, My Lord John garnered a mostly negative reception from contemporary readers and literary critics, who felt that it lacked narrative flow and was inferior to Heyer's Regency novels.

Georgette Heyer is best known for writing romantic stories set in the Regency era, but her body of work encompassed many different historical periods, including the English Civil War and the Middle Ages.

Her impatient readers continually clamoured for new books, however; to satisfy them and her tax liabilities, Heyer interrupted herself to write Regency romances,[2][3] such as April Lady (1957)[4] and Charity Girl (1970).

"[6] Rougier stated that the perfectionist Heyer prepared for the trilogy by embarking on holistic research that covered "every aspect of the period," including its wars, social conditions, and heraldry.

Now twenty-two, King Richard takes the reigns of government back into his own hands, appointing new favourites labelled "contemptible foppets" by his uncle John of Gaunt, 1st Duke of Lancaster.

John of Lancaster – the third eldest son of Henry of Bolingbroke – resides at Kenilworth Castle with his mother Countess Mary and three brothers Harry, Thomas, and Humfrey.

The boys are visited by their grandfather, John of Gaunt, and a large retinue that includes his mistress Katherine Swynford, his daughter Lady Elizabeth, and his three Beaufort sons.

Perceiving in his third son this talent for administration, King Henry had bestowed wide powers on him, leaving it to him to seize recalcitrant peers, punish transgressors, pardon penitents, appoint new offers, and negotiate truces.

As a teenager John proves his worth and is gradually granted positions of authority, first as Master of the Falcons, then as Lord Warden of the East Marches and Constable of England.

[18] Geneva Stephenson of the Columbus Dispatch likened My Lord John more to a historical narrative than a novel, only deciding on the latter category due to the work's "in-depth characterisation, movement, colour, [and] motivation.

"[25] The year of its release in 1975, Library Journal contributor Eleanore Singer praised it for being "well-documented historical writing," though she felt that "as a novel, it doesn't have enough dramatic or narrative flow to keep it from being often boring.

"[26] Jane Aiken Hodge of History Today, while praising Heyer's Regency novels as "triumphs of a language that never was on sea or land," thought that My Lord John was "less successful.

Franklin of The Times Literary Supplement opined that because the novel ended before the "most interesting parts of John of Bedford's career," it "has an air of anticlimax about it, and more than once themes are indicated which vanish inexplicably.

"[20] In a 2008 contribution for The Times, Hilary Rose praised Heyer's Regency novels but found My Lord John to be "oddly difficult, possibly on account of it being concerned more with medieval history than masquerade balls at Vauxhall Gardens.