hakkapeliitat) is a historiographical term used for a Finnish light cavalryman in the service of King Gustavus Adolphus of Sweden during the Thirty Years' War (1618 to 1648).
In the early 17th century the cavalry led by the Field Marshal Jacob De la Gardie participated in campaigns against Poland and Russia.
The Hakkapeliitta cavalry men led by Field Marshal Gustaf Horn were vital to the Swedish victories in Germany during the Thirty Years' War.
They were equipped like the typical harquebusier light cavalry of their era; armed with a broadsword and two wheellock pistols and protected by a buff coat and a pot helmet.
They would attack at a full gallop, the troopers on the front rank firing their pistols at near-contact distance and the whole formation crashing through the enemy at sword point.