It was only after his failed attempts in multiple Dutch schools, selling art throughout Europe, and a brief foray preaching the bible to coal miners in Belgium, that an irascible, twenty-seven year old Vincent van Gogh turned to his true calling, one that would carry his name and vision down a path toward immortality.

Today, the iconic name shepherds the masses to galleries and museums the world over. The oeuvre of his work, which sells in the millions, is instantly recognizable for its revolutionary style in theme, technique, and color.

That he only painted during the last ten years of his life is but one of the many astounding facts in his extraordinary life. With his work, Van Gogh wanted to leave his gift to the world. “My plan is not to spare myself, not to avoid a lot of emotions or difficulties. It’s a matter of relative indifference to me whether I live a long or a short time. I’m concerned with the world only in that I have a certain obligation and duty, as it were — having walked the earth for thirty years — to leave a certain souvenir in the form of drawings or paintings in gratitude,” he wrote.

And yet, what’s lesser know of the mad genius from Zundert, Holland is the trove of letters he also left behind. Of the nearly one thousand surviving letters Vincent van Gogh wrote between 1872 and 1890, nearly all were to his younger brother, Theo. Four years Vincent’s junior, Theo became his older brothers confidant and supporter—both mentally and financially—often acting as a buffer between the artist and the ‘hostile world.’

In his letters to Theo, the pure tempest of Van Gogh’s fragile mind can be read on the page. What begins as the innocent joys of employment and the nostalgia of days past gives way over the years to dark depression and deep anxiety, all bound in a relentless ambition to succeed in his artistic revolution.

In a letter written to Theo in December 1883, Van Gogh expressed his reason for writing. “It may be politic to keep what one thinks to oneself, however it has always seemed to me that a painter, above all, had a duty to be sincere - you yourself once pointed out to me that whether people understand what I say, whether people judge me rightly or wrongly, didn’t alter the truth about me.” The truth about Vincent van Gogh, the very core of his struggles, beliefs, madness, and ambitions can be found in his collected letters, Ever Yours: The Essential Letters (Yale University Press, December 2014).

One of the numerous reasons Van Gogh became such a prolific letter writer was the simple fact that with every city he lived in, finding and keeping friends proved a task too difficult for the sensitive, disruptive soul. Summed up in a letter to Theo from a small provincial town in Belgium, Vincent wrote, “Like everyone else, I have need of relationships of friendships or affection or trusting company.”

The first letters begin in 1872, and reading them, it becomes apparent just how close this brotherly bond was from a young age (a bond which would carry through into death). When Theo first obtained a job at the same art dealership as his brother, Goupil & Cie, Vincent is gushing with pride and happiness. “My hearty congratulations to you on this day, may our love for one another only increase as we get older. I’m so happy that we have so much in common, not only memories of the past but also that you’re working for the same firm...I wish you well today, old boy, and begin a happy and blessed year. These are important years for us both, years on which much already depends. May everything turn out well.”

Yet, everything did not turn out well. And after moving Vincent through various locations, including Paris and London, his employment was eventually terminated in April 1876. To help soften the blow, Vincent turned his mind toward literature, filling his letters to Theo with quotes and analysis of Keats, and Dickens, Shakespeare and Zola.

Utterly dejected, embarrassed to face his strict mother and father, Van Gogh turned his manic attention toward the word of God, deciding to become a preacher of the Christian gospel. Gone were the quotes from his literary heroes, now was the time for God’s work. In letters to Theo, Vincent would preach to younger brother the virtues of life. “We are pilgrims, our life is a long walk or journey from earth to heaven.”

His pursuit of religion was, once more, met with failure. When, in late summer of 1880, Van Gogh announced himself an artist, his previous months of letters signaled a desperate need to find a direction in life. He wrote to Theo, “If I do nothing, if I don’t keep on trying, then I’m lost, then woe betide me. But what’s the ultimate goal, you’ll say. That goal will become clearer, will take shape slowly, as the croquets becomes a sketch and the sketch a painting, as one works more seriously, as one digs deeper into the originally vague idea, the first fugitive passing thought, unless it becomes firm.”

The letters to follow, in which Van Gogh the artist begins to tease out all the possibilities of his pencil, show a man who is devoting himself to the cause of art. “Careful study and the constant and repeated copying of Bargue’s exercises have given me an insight into figure drawing. I have learned to measure and to see and to look for the broad outlines, so that, thank God, what seemed utterly impossible to me before is gradually becoming possible now. I no longer stand as helpless before nature as I used to do.” Here, we learn the approach Van Gogh took in teaching himself how to draw. From Charles Bargue’s sketchbook, Vincent sets the first bricks in the path toward mastery.

Upon reading his letters, it becomes apparent Van Gogh’s life’s work in art and his mental illness worked in unison. When feeling sick, his artwork became greater, bolder. “The more I become dissipated, ill, a broken pitcher, the more I too become a creative artist in that great revival of art.”

Yet, in pursuit of that ‘great revival of art,’ his anxiety, depression, and overall health began to deteriorate. “The fact that I have a definite belief as regards to art means that I know what I want to get in my worn work, and that I’ll try to get it even if I go under in the attempt.”

No one understood Vincent’s pains better than Theo. The younger brother would try everything in his power from a distance to subdue the roaring flames of passion. Oftentimes, to no avail. “I get very cross when people tell me that it is dangerous to put out to sea,” the artist wrote Theo once when his younger brother was attempting to help. “There is safety in the very heart of danger.”

Through their correspondences, Theo, the successful young art dealer of Paris, urged his brother to display the palette and techniques in vogue, such as subtle care, and delicate finish. If only Vincent wouldn’t apply such thick paint to his canvas, if only he would slow down and work as a professional, maybe then, Theo argued, would collectors come to the door. Blind with his own vision, Vincent simply responded, “I am a fanatic! I feel a power within me...a fire that I may not quench, but must keep ablaze.”

Almost in a premonition of the success to come, a success he would never realize in his lifetime, Vincent again took to the pen in arguing his methods to Theo. “You can see, then, that I’m working like mad, but for the moment it isn’t giving very heartening results. But I have hopes that these thorns will bear white flowers in their time, and that this apparently sterile struggle is nothing other than a labor of giving birth. First pain, than joy afterwards.”

Starting as an artist in The Hague, we follow Van Gogh’s sincere struggles coping with his failures in life. In a heartfelt letter to Theo mere days after his father expelled him from of the family house in Etten, Holland, Van Gogh wrote, “What am I in the eyes of most people? A nonentity or an oddity or a disagreeable person — someone who has and will have no position in society, in short a little lower than the lowest. Very well, then through my work I’d like to show what there is in the heart of such an oddity, such a nobody.”

We chart his progress, if not in mind, certainly in art, as he moves, in 1886, to Theo’s Montmartre apartment in Paris. It’s here, for the first time, Van Gogh begins preliminary sketches of the now famous sunflower series; a plant he felt a special kinship with. Much like himself, the August sunflower was a late bloomer. What’s more, the flower followed the arc of the sun throughout the day; much in the same way Van Gogh wished himself to follow the path of God.

From Paris we move with Van Gogh to the south of France, in the town of Arles, where, he wished to produce works that would serve as, “a consolatory art for distressed hearts.” After inviting fellow artist Paul Gauguin down to Arles to work and paint side by side, the short stint together in the Yellow House of Arles, culminated in the now infamous slashing of Van Gogh’s ear.

After that fateful December night in Arles, 1888, Van Gogh was sent to a hospital in to be treated for his ear, then to the Saint-Paul Asylum in Saint-Rémy, a town in Provence, France. It was in Saint-Rémy where Van Gogh sends his brother word of how all his sacrifice may soon be for nothing in this life. Yet, the ever-visionary Van Gogh still feels the possibility of acclaim after his imminent death. “It is precisely in learning to suffer without complaining, learning to consider pain without repugnance, that one risks vertigo a little; and yet it might be possible, yet one glimpses even a vague probability that on the other side of life we’ll glimpse justifications for pain.”

“I want to paint what I feel,” he said to Theo, “and feel what I paint.” After reading Ever Yours, if nothing else, one can start to understand how such a fanatic mind could produce such fanatic art. No one can understand the depths, struggles, or ‘sorrowful, yet always rejoicing’ paintings of Vincent van Gogh without the accompanying letters helping decode the labyrinth that he alone created.