Elsa Einstein (18 January 1876 – 20 December 1936) was the second wife and cousin of Albert Einstein. Their mothers were sisters, thus making them maternal first cousins. The couple were also paternal second cousins (i.e. their fathers were first cousins). Born an Einstein, Elsa gave up the name when she took the surname of her first husband, Max Löwenthal; she and her daughters reverted to her maiden name after Elsa and Löwenthal's 1908 divorce.
