When Albert Einstein met Second Wife Elsa

After being childhood playmates and growing up together, both married other people, before realising their true feelings for each other in adulthood. What makes their relationship particularly interesting is the fact they were also cousins, their families intertwined.

The 70th anniversary of Einstein’s death in April 2025 has sparked renewed interest in the celebrity couple of yesteryear, with the modern cultural reference labelling him the “rockstar of science”.

Relatively little was known about his personal life until 2006, when historians unearthed 1,300 letters he had written, spanning four decades. The correspondence with Elsa and other family members while Albert was away touring and lecturing shattered the myth he was cold towards his wife and children. Instead, they painted a picture of a caring husband and father, who loved his family and acknowledged his weariness at being continually in the public eye due to his groundbreaking scientific work. He also recognised his own weaknesses and was open about his failings as a husband.

After marrying Elsa, she began managing his financial affairs and remained loyal and true to her husband throughout their long relationship.

Where was Albert Einstein born?

Almost everyone has heard of the man behind the theory of relativity but today, his face has become familiar after being hijacked by advertising agencies to promote their products on TV.

The real Albert Einstein, born in Germany in March 1879, was a genius, with an estimated IQ of around 160, compared with the average of between 90 and 109. His parents, engineer Hermann and housekeeper Pauline Einstein (nee Koch), were Ashkenazi Jews from Württemberg.

One of six siblings, Hermann excelled at school in Stuttgart and aspired to study mathematics at university, but the family’s poverty meant further education wasn’t an option. He left school to start work instead.

Early life of Albert Einstein

The family moved to Munich in 1880, where Hermann and his brother Jakob founded Elektrotechnische Fabrik J Einstein & Cie to manufacture electrical equipment. Albert’s interest in physics was sparked as a child when Hermann gave him a compass and he began to consider how “something deeply hidden” existed.

The first meeting between Albert Einstein and Elsa took place when they were children. Born in Hechingen in January 1876, Elsa was related to Albert on both her father’s and mother’s side of the family. Their lineage was complex: Elsa’s father, Rudolf Einstein, was Albert’s first cousin once removed. This was because Rudolf’s father Elsa’s grandfather Rafael Einstein, was Hermann’s uncle. This led to the unusual situation whereby Elsa was born an Einstein, and her married name remained the same. To complicate matters further, Elsa’s mother Fanny (nee Koch) was Albert’s mother’s older sister!

The extended family enjoyed a close bond, and all the children played together, spending plenty of time together growing up. Their shared background and early interactions during Elsa’s visits to see her cousin “Albertle” in Munich led to a close friendship until 1894, when Albert, 15, emigrated to Milan with his family.

First marriages

Elsa, then 18, met Berlin textile trader Max Löwenthal and they married in 1896. They had two daughters, Ilse and Margot, born in 1897 and 1899 respectively. The couple drifted apart, with Max taking a job in Berlin and Elsa remaining at the family home in Hechingen with their daughters. They divorced in May 1908 and Elsa reverted to her maiden name of Einstein.

Albert married Mileva Marić in 1903 and they had two sons, Hans and Eduard, born in 1904 and 1910 respectively. However, their marriage was unhappy, and he described it as “misguided”. Mileva and Albert separated in 1914, and she returned to Zurich, taking Hans and Eduard with her. They were divorced in February 1919, having lived apart for five years.

Correspondence suggests Albert and Elsa were back in touch in 1912.

Albert and Elsa married life

The childhood friendship between Albert and Elsa evolved into romance and they were married in June 1919, with Albert becoming stepfather to her two daughters, Ilse and Margot. They settled in Berlin in 1929, when Albert’s career was at its peak.

Having written his first scientific papers in 1900, he had become the world’s leading theoretical physicist. In 1908, he became a lecturer at Berlin University, followed by a professorship at Zurich University. He later joined the Prussian Academy of Sciences, became director of Kaiser Wilhelm Institute for Physics and chairman of the Humboldt University of Berlin.

The world-famous scientist became renowned for his groundbreaking research and theories, including relativity and gravity; E=MC2 relating to mass and energy; Brownian motion about the movement of particles; gravitational waves and hundreds of other subjects. During his lifetime, he published more than 300 scientific papers and around 150 other papers, as well as writing books, journal articles and research material.

Albert and Elsa’s personalities complemented each other, with her sensible and practical nature leading to her managing the family’s finances, leaving her husband to work unhindered.  Extremely supportive towards Albert, Elsa was also described as “gatekeeper”, protecting him from charlatans and other unwelcome visitors.

Albert received the prestigious Nobel Prize in Physics in 1921. He reportedly gave his ex-wife Mileva the prize money to invest in their two sons, who had been brought up by their mother.

Einstein’s letters

For almost a century, very little was known about the private lives of Albert and Elsa, with his reputation as an academic leading to speculation he was cold and detached. However, all this changed when letters he had written between 1912 and 1955 were released by the Hebrew University in Jerusalem.

His stepdaughter Margot donated the letters; on condition they must remain private for 20 years after her death in July 1986. Her wishes had been respected, permitting their release in 2006. They confirmed Elsa continued to support her husband, despite the strain of his career and long periods apart due to his touring the US, Asia, the Far East and Europe. They wrote to each other almost every day, with Albert missing family life. While in Prague, he told her, “Soon, I’ll be fed up with ‘relativity’. Even such a thing fades away when one is too involved in it.”

He also spoke of his unhappiness at women “chasing” him and “getting out of control”, seemingly reinforcing the “rockstar” comparisons of today, saying he was about to tell one that she should “vanish immediately”. There has been speculation among historians about Albert’s alleged infidelity, but he remained with Elsa until she passed away and he never remarried.

In 1933, the Einsteins emigrated to New Jersey, US, moving to a new house on Mercer Street. Sadly, they had little time to enjoy their later years due to Elsa passing away in 1936, a year after being diagnosed with terminal heart and kidney problems. Albert threw himself into his work until he died aged 76 in April 1955, leaving his legacy that continues to inspire the world of science today.