After 1806 Gustav Kirchenpauer's father faced ruin on account of the Napoleonic trade restrictions known as the Continental System, the city having fallen under French control earlier . The family therefore left Hamburg in 1810, moving to Saint Petersburg in 1810. Unfortunately the boy's mother died the same year: two of his brothers had also died in infancy. Kirchenpauer and his two remaining brothers were sent to live with Jacob von Krause who was married to their father's sister, Julia (and thereby, by marriage, the Kirchenpauer boys' uncle). The extended family fled to London during the Autumn of 1812 to avoid the French invasion, but were able to return the next summer. The three brothers stayed on with their otherwise childless aunt and uncle in Saint Petersburg, where they grew up while their own father pursued his itinerant mercantile career.