THE year was 1915. War and privation had come to Germany.
Meanwhile, in Berlin, a solitary man struggled with the equations for a new theory of gravity.
"I have been laboring inhumanly," Albert Einstein, then 36, wrote to a friend in his native German. "I am quite overworked."
His fellow scientists, he complained in a letter contained in a newly published collection of his personal correspondence, were behaving abominably, either "trying to poke holes" in his theory or competing with him to finish it first.
At the same time, he was estranged from his two young sons, who were living in Switzerland with their mother, from whom Einstein had separated the year before. He was romancing his cousin Elsa Lowenthal, whom he would later marry, and was stressed about money. His stomach was acting up.
"Come, dear old friend, Lady Resignation, and sing me your familiar old song so that I can continue to spin quietly in my corner," he lamented in one self-pitying note.
In 1915, as Western civilization teetered on the brink, Albert Einstein stood at the threshold of a scientific achievement so bold that it would forever change him and the world.
His general theory of relativity, which described how large bodies warped space and time, would revolutionize people's ideas about the physical world and guarantee that the rest of his life would be lived in the glare of a celebrity that made heads of state and Hollywood stars go tongue-tied in his presence.
The gem of this new collection, published by Caltech and Princeton University, is a treasure trove of personal letters that have been locked away for almost a century and are now shedding fresh light on the man and his work at this moment of transformation.
Einstein's stepdaughter Margot donated 130 letters, written in German, from and to his closest friends and family members. Margot, who died in July 1986, had specified that they not be released to the public for 20 years after her death.
These letters portray the greatest thinker of the 20th century at the height of his powers not as a triumphant genius but as a working man struggling to make ends meet while the world around him threatened to devolve into chaos.
This image of a man who could be as insecure as he was accomplished, as spiteful as he was open-hearted, runs counter to two popular notions of Einstein.
One image is the gentle antiwar symbol whose fright-wigged visage smiled down from a thousand dorm rooms. The other is of Einstein the distracted genius too occupied with great thoughts to match his socks.
In fact, according to Walter Isaacson, former managing editor of Time magazine and author of a forthcoming biography, Einstein in 1915 was "awesomely human."
He would never again be so poor, nor so vulnerable, as he was in the spring, summer and fall of 1915.
ALBERT Einstein met Mileva Maric at the Zurich Federal Institute of Technology in 1896, when he was just 17. He was the bright young student who cut class and didn't much care for the antiquated ideas of his professors.
Mileva was three years older, walked with a limp, was too brainy and wasn't Jewish. They fell in love, but his parents didn't like her. The couple were independent-minded and willfully modern.
Mileva gave birth in 1902 to a girl the couple named Lieserl, but she was sent away, some scholars say, out of concern that the out-of-wedlock baby might harm Einstein's career. Lieserl is believed to have died the next year.
Einstein moved to Bern to take a job at the Swiss patent office, and married Mileva in 1903 after his father consented to the match on his deathbed. The couple had a second child the next year, a boy they named Hans Albert.
Mileva gushed with happiness in those early years. "I am even closer to my sweetheart, if it is at all possible, than I was in our Zurich days," she wrote to a friend, Helene Kaufler.
She was especially thrilled with the publication in 1905 of his first important work, which she accurately predicted to friends would make him famous.
He presented three papers that scientists still rank among the greatest bursts of creative genius in history. A paper on Brownian motion would explain the apparently random motion of particles in liquid. The second paper, on the photoelectric effect, described light not as a wave but as possessing the characteristics of a stream of particles. Lastly, his paper on special relativity gave the world the equation E=mc2.
But their love eventually began to fade and by the summer of 1914, when Einstein moved to Berlin to become director of the Kaiser Wilhelm Institute of Physics, their relationship had deteriorated. Mileva rightly suspected him of carrying on an affair with Elsa, and he began contemplating divorce.
Einstein dictated a set of conditions to his wife: She would have to forgo intimacy, serve his meals in his room, "desist immediately from addressing me if I request it ... leave my bedroom or office immediately without protest if I so request."