He was probably born in Sweden, and possibly died at Drottningholm Palace, in Lovön parish, Stockholm county.
During his time spent in Rome, he had the opportunity to study Peter Paul Rubens and other Netherlandish masters.
En route to England, he possibly stepped in Paris, where he might have studied Charles Le Brun.
His most notable surviving works are the vast allegorical and mythological paintings (dating from 1685 to 1695) wherewith he decorated Drottningholm Castle.
In Rome, Johan Sylvius also drew a pen and wash drawing on paper in gray and black, executed with pencil and brown ink, called Gravmonument över Ferdinand van den Eynde, or 'Tomb monument over Ferdinand van den Eynde,' after François Duquesnoy's original in the church of Santa Maria dell'Anima in Rome.