Twain wrote that this was his favorite of his own books. He initially published it under a pseudonym, hoping for a more serious audience. It is a remarkably devout work for so ascerbic and skeptical an author, reading like none of his others.
With Joan of Arc love of country was more than a sentiment--it was a passion. She was the Genius of Patriotism--she was Patriotism embodied, concreted, made flesh, and palpable to the touch and visible to the eye.
Love, Mercy, Charity, Fortitude, War, Peace, Poetry, Music--these may be symbolised as any shall prefer: by figures of either sex and of any age; but a slender girl in her first young bloom, with the martyr's crown upon her head, and in her hand the sword that severed her country's bonds--shall not this, and no other, stand for PATRIOTISM through all the ages until time shall end?
The "personal recollections" are those of Louis de Conte, Joan's secretary and (in fiction) her childhood companion. At the end of his life, decades after the wars, her martyrdom and rehabilitation, he recounts all the incidents of her life from start to finish in loving, devoted detail. The visions and miracles are treated as literal truth. Twain never uses Joan as an object of his wit, although the familiar irony peeks through is his acounts of peasant life, the shabby court of Charles VII, and especially in his anger at the Church officials who tried and condemned the Maid of Orleans.
Men of a certain age sometimes become infatuated with her virgin purity and soldierly courage. It happened to Churchill and it happened to Twain. She is presented as a sort of militant Virgin Mary, a force both unstained and effective in world affairs. Chesterton put Mary herself in that role in his long poem about King Alfred, when the King saw her in a vision above the battlefield:
Over the iron forest He saw Our Lady stand, Her eyes were sad withouten art, And seven swords were in her heart-- But one was in her hand.
...and he knew the tide had turned.
Quite striking are the political images which resonate beyond the Hundred Years' War: the degradation of living in an occupied country, of having unworthy, scheming and cowardly leaders, and of being betrayed by them after giving everything for their stuggle.
The final third of the book is a detailed and somehat plodding account of her trial. Twain's version of her abjuration just before her execution is troubling. He treats it as an error caused by fatigue and bewilderment. That seems to miss one of the dark mysteries of the faith: even Christ on the cross seemed lost for a time, and it is not unreasonable for saints and martyrs to share something of that experience.
Morbid curiosity makes us wonder what Joan endured in prison, surrounded by enemy guards and without the female companions she asked for repeatedly. Not torture, perhaps, because we have records of the attempts to threaten her with that, but Twain has the narrator say:
Did Cauchon hint to the Engish guards that thenceforth if they chose to make their prisoner's captivity crueller and bitterer than ever, no official notice would be taken of it? Perhaps so; since the guards did begin that policy at once and no official notice was taken of it. Yes, from that moment Joan's life in that dungeon was made almost unendurable. Do not ask me to enlarge upon it. I will not do it.
I would never have suspected Twain of being sympathetic toward the French nation, or toward parish priests and monarchs, but he presents many such startling sentiments.