English guitar is a stringed instrument, a type of sister (or cittern), which was popular in many places in Europe from around 1750-1850. The instrument was also known in Norway as a guitarre. There are many examples in Norwegian museums, including at the Norsk Folkemuseum. The English guitar has a pear-shaped body, a flat base, and a short neck.
Hannu Annala, Heiki Mätlik (2007). "Composers for other plucked instruments: Rudolf Straube (1717-1785)". Handbook of Guitar and Lute Composers (Translated by Katarina Backman ed.). Mel Bay. p. 30. ISBN 0786658444. ISBN 9780786658442.