Peter the Great first established the two senior units of the eventual Imperial Guard, the Preobrazhensky and Semyonovsky infantry regiments. Peter formed these two regiments as part of his professionalization of the Russian army after its disastrous defeat by the Swedes at the Battle of Narva, during the early phases of Great Northern War. He was influenced, too, by his distrust of the Streltsy, who had risen against him repeatedly, both during his childhood (which traumatised him) and during his reign.