Gotthold Eisenstein was born on April 16, 1823, in Berlin, Germany. His parents were Johan Konstantin Eisenstein and Helene Pollack. His father, who had served eight years in the Prussian army, tried his hand at various commercial enterprises, including manufacturing, but without financial success. Not until late in life did he begin to make a decent livelihood. Eisenstein’s brothers and sisters, born after him, died in childhood, nearly all of meningitis, which he also contracted.
His interest in mathematics, awakened and encouraged by a family acquaintance, began when he was about six. Early, too, he showed musical inclinations that continued throughout his life and that found expression in playing the piano and composing.
In the summer of 1842, before completing school, he accompanied his mother to England to join his father, who had gone there two years earlier in search of a better livelihood. In neither England, Wales, nor Ireland could the family gain a firm footing. By around mid-June 1843 Eisenstein and his mother were back in Berlin. His parents were now living apart, and from then until his death Eisenstein stayed with his mother only briefly from time to time.