When Hugh and Mirabel Cecil’s book In Search of Rex Whistler was published in 2012, the late Brian Sewell reviewed it with typical insight and lack of generosity. Despite recognising the artist as an extraordinary talent and perhaps the inventor of neo-romanticism, he regretted that Whistler would never be taken sufficiently seriously and pronounced it the last book on him.

Happily the Cecils have now proved Sewell wrong several times over. Hugh Cecil’s father, David, was a close friend of the artist, and these volumes seem in part to constitute the continuation of a family’s love for a man who inspired affection wherever he went. Along with a recent book by Anna Thomasson on Whistler’s friendship with Edith Olivier, exhibitions in London and Salisbury and a growing interest in Whistler’s work at auction, they suggest there may even be a revival under way.

It is true that there are challenges. Whistler’s most significant works are probably his murals, and apart from the one magnificently restored in the Tate restaurant (where the food does not remotely live up to the walls) they are slightly tricky to access. The finest is in Plas Newydd. Another is at Dorneywood, currently the Chancellor’s weekend retreat and open to the public only for a fortnight each year. Otherwise, having to earn his own way in the world, Whistler spent much of his time engaged in commissions for book and magazine covers as well as stage-designs. And then there is the terrible fact that having joined up at the start of the war — and after years training as a tank commander — Whistler was killed in Normandy on his first day of action in July 1944, aged 39.

His technical skill was dazzling from the start. In his first year at the Slade Whistler copied some of his favourite poems into a notebook and decorated them with striking and often moving watercolours. His devoted brother Laurence published a facsimile of An Anthology of Mine in 1981 as part of his constant efforts to keep Rex’s reputation alive, but this return to print is even more handsome. Indeed it is a treasure of contemporary bookmaking. The other two Cecil volumes do not greatly add to their 2012 book, but their purpose appears to be to act as shorter introductions and to handsomely bring back into print examples of their subject’s work which have become difficult to find.

They are reminders of just how much Whistler achieved in the half a life that he had. The portraits from the war years — particularly the self-portrait on his first day in uniform, and some of his fellow soldiers — must count as among the greatest British portraits from those years. The often cartoonish character of his early figures has transformed into a fully-controlled and mature mastery of oils. The fact that the works are so few means that as we read here of pieces he put together for the amusement of his fellow soldiers (such as the set he painted for a ‘security show’ while his regiment was awaiting embarkation) one wants to know every detail.

Despite having a huge circle of friends, Whistler was always unlucky in love. But it was probably not for that reason alone that he wrote to one female friend, after the last party he attended before leaving for France:

How much I loved every minute of that lovely, crazy, unnecessary, enchanting evening, filled with real laughter and affection and friendship, yet, for me, somehow grief-stricken. In the midst of so much happiness and fun, I felt a desolate sense of loneliness.

Today too few of Whistler’s works are on public display — or prominently enough displayed when they are. His position in British art remains badly underestimated. But surely the next book that needs to be added to the growing bibliography is a volume of his letters. Preferably with facsimiles of those in which he entertained his friends with exquisite drawings of what he, or his imagination, had seen. From an artist around whom feelings of ‘what might have been’ will always remain, making available as widely as possible what might otherwise have slipped into oblivion has passed from being the role of Whistler’s friends into that of anyone who cares about 20th-century British art.