He owned a silk manufacturing factory in his native city, was co-founder of the German Bank and of the Bergisch-Märkische Bank, and Persian Consul. He acquired much of his business experience travelling abroad, lived in Paris and London, and made trips to the U.S.A., Constantinople and Asia Minor. On his first journey to America, he met in New York Mary L’Estrangge whom he married on September 4, 1852. The newly-married couple settled in Elberfeld, Germany, where their seven children were eventually born.
Noted as a linguist, he spoke French and English without accent. A far-sighted business-man, he was also known for his warm hospitality, broad-mindedness, and readiness to help others, even when their views differed from his own.
On July 27, 1884, the Germania Theosophical Society was organized at his home at Elberfeld, Platzhoffstrasse 12, with Dr. Wilhelm Hübbe-Schleiden as President, his wife Mary as Vice-President, and his son Franz Gebhard as Corresponding Secretary. All the members of the Gebhard family, except their daughter, joined the Theosophical Society.
On August 17, H. P. Blavatsky, Col. Olcott, Mohini Chatterjee and Babaji, who were in Europe, went to Elberfeld and stayed with the Gebhards until October. During this time their home became the center of Theosophical activities. While Gustav was of course the official host during these visits, the most dynamic personality of the household was Mary, who combined refinement and culture with rare capacities for occult studies. On August 25, 1884, Gustav received a letter from Master K.H.
A couple of years later, in May and June, 1886, Mme. Blavatsky stayed with the Gebhards again.
- A Letter from Mahatma Koot Hoomi to Gustav Gebhard at Blavatsky Archives Online.
- Helena Petrovna Blavatsky, Collected Writings vol. VI (Wheaton, IL: Theosophical Publishing House, 19898), 434.