IVsevolod Dmitrievich Zinserling was born on September 20, 1891, in St. Petersburg. His father, Dmitri Petrovich Zinserling, a descendant of immigrants from the south of Germany or Switzerland, who received hereditary nobility, worked all his life as a teacher of mathematics and, as an inspector of the famous Gurevich Gymnasium, had the rank of actual state councilor. Dmitry Petrovich was also the author of scientific research on the history of mathematics in ancient Egypt, manuals on statistics, and algebra textbook, which was republished many times. His mother, Olga Ivanovna (nee Semenova), ran the household and raised four children. There was a creative atmosphere in the family, all had artistic talents, loved and knew nature well. The elder brother Boris Zinserling, a graduate of the Academy of Fine Arts, an officer, after the Civil War, found himself in Warsaw, where he became a professor and author of projects to restore many architectural masterpieces in the postwar period. His younger brother Yuri (George) Zinserling, a doctor of biological sciences, a botanist, one of the founders of a new scientific trend - geobotany, was arrested in 1938 when he was acting director of the Botanical Institute and soon died in custody. His sister Nina was an artist who died at a young age.