Carl Johan "Janne" Jakob Keyser, born on 5 July 1821 in the parish of Slaka, Östergötlands Län, died on 7 April 1895 in Norrköping, was a Swedish agricultural scientist and lecturer.Keyser enrolled at Uppsala University in 1841 and graduated with a Master's degree in philosophy in 1848, after which he was reappointed as a lecturer in agricultural chemistry at Uppsala University. In 1853-54 he undertook a scientific journey through Germany and France on a scholarship and later became a teacher at the technical school in Norrköping. In 1877-88 he was a lecturer at the same school. Keyser published a number of scientific papers.
The family roots of translator, author and editor Albert George Viktorsson Trolle lie within sight of the fabled Yew Island, where Wieland is said to have had a smithy. These roots, in the long-disputed border region between Denmark and Sweden, have contributed to his enthusiasm for historical subjects since early childhood.He now lives with his wife and three children in the southernmost reaches of historic Iarnwith.