Mileva was born in Titel in Vojvodina, a northern province of Yugoslavia, of Serbian parents. At the age of twenty-one, she entered the Swiss Federal Polytechnic, in the same year (1896) as Einstein, who was three and a half years younger than her. She was, in that year, the only woman beginning studies in the mathematical section of the School for Mathematics and Science teachers. Einstein and Mileva met as students. They married on January 6, 1903. The two witnesses at the quiet wedding were the original members of the Olympia Academy, Maurice Solovine and Conrad Habicht. There was no honeymoon, and after the celebratory meal in a local restaurant the couple returned to their new home on 49 Kramgasse, close to Berne's famous clocktower.
After their marriage, Mileva subordinated her professional goals to Einstein's. Mileva entered Einstein's life in a crucial period of his scientific achievements and helped him in his endeavour. Einstein's marriage to Mileva was an intellectual partnership. They had two sons. Their daughter Lieserl was born before their marriage and died in childhood. At the time of Mileva's death in 1948 her oldest son Hans Albert was a professor in hydraulic engineering at the University of California at Berkeley. The other son was psychotic, and Mileva cared for him until she died.
Mileva spent the winter semester of 1897 to 1898 in the German city of Heidelberg. In a letter to Einstein written from Heidelberg, Mileva expressed her fascination with a lecture of about the relationship between the velocity of a molecule and the distance traversed by it between collisions, a topic relevant in Einstein's studies of Brownian motion. Einstein admired Mileva's calm independence and intellectual ambitions. He considered himself lucky to have found Mileva, "a creature who is my equal and who is strong and independent as I am". Later, while working on the subject of electrodynamics of moving bodies, Einstein wrote to Mileva about "our work on relative motion".
The extent of Mileva's contribution to Einstein's work is controversial. According to Evan Harris Walker, a physicist, the basic ideas for relativity came from Mileva. Senta Troemel-Ploetz, a German linguist, says that the ideas may have been Albert's, but Mileva did the mathematics. On the other hand, John Stachel, keeper of Albert's letters, says that Mileva was little more than a sounding board. The case for Mileva as co-genius mostly depends on letters in which Albert referred to "our" theory and "our" work and on a divorce agreement in which Albert promised her his Nobel Prize money. Biographer Abram Joffe claims to have seen an original manuscript for the theory of relativity which was signed, "Einstein-Maric".
Life and love had an unequal effect in lives of Einstein and Mileva as man and woman, and as scientists. Einstein left her for another woman and Mileva spent the rest of her life struggling to support herself and her children, including a psychotic son.