 Complete the following phrase:  During the Finnish War of 1808-1809 he distinguished himself as a brave and prominent officer. When Cronstedts army retreated from Mikkeli to Iisalmi and Oulu through Leppävirta March 1808, Duncker commanded the armys rearguard. During the Battle of Pulkkila 2 May 1808 he distinguished himself so well that Johan August Sandels gave him the honorary assignment to bring the news of the victory to the Swedish king. Shortly after, he was promoted to Major. In June 1808 he captured a large transport of supplies to the Russians. During the 