Sebastian Albert Freiherr von Sack (died 1828) was a German explorer and a chamberlain of Prussian nobility. In June 1821 he was honored with the title of "Graf (count)".
In 1805 he travelled to Surinam, where he made observations of the fauna, flora and local customs of the population. On his return journey back to Europe, he visited Washington DC, Philadelphia, New York City, Boston, et al. As a result of his travels he published Beschreibung einer Reise nach Surinam und des Aufenthaltes daselbst in den Jahren 1805, 1806, 1807 sowie von Rückkehr des Verfassers nach Europa über Nord-Amerika. In 1810 this treatise was translated into English as "A narrative of a voyage to Surinam; of a residence there during 1805-1807; and of the authors return to Europe by the way of North America".
^Regarding personal names: Freiherr was a title before 1919, but now is regarded as part of the surname. It is translated as Baron. Before the August 1919 abolition of nobility as a legal class, titles preceded the full name when given (Graf Helmuth James von Moltke). Since 1919, these titles, along with any nobiliary prefix (von, zu, etc.), can be used, but are regarded as a dependent part of the surname, and thus come after any given names (Helmuth James Graf von Moltke). Titles and all dependent parts of surnames are ignored in alphabetical sorting. The feminine forms are Freifrau and Freiin.