He wrote extensively on the customs and language of peoples affected by European colonization in America and Oceania.
He made his career in the army, but from an early age was interested in the history and peoples of foreign lands.
A reviewer wrote, "The author shows close familiarity with the literature of the subject, and every statement is substantiated by authoritative reference.
[2] He worked on his findings for several years, but was called back to military service with the outbreak of World War I (1914–18).
After being discharged he moved to Ahrensburg, Holstein where he built a large library on the history of exploration of America and Oceania.