A lokacin yakin 1812, rundunar ta yi yaƙi a yakin Boyarshchina, Golovshchina, inda ta rasa mutane 160, da Svolne, inda ta rasa mutane 200. A lokacin Yaƙin Polotsk na Farko a ranar 18 ga Agusta, wanda aka bayyana a matsayin babban babban aikinsa na farko, ya rasa jami'ai goma sha huɗu da sama da maza 400 amma ya sami damar kawar da hare-haren Faransa da yawa da kuma ci gaba da koma baya cikin tsari. An ji rauni sau biyu a lokacin aikin, Ulrichsen ya kasance tare da rundunar kuma ya jagoranci hare-haren da aka yi a lokacin da aka janye. Don ayyukansu a wannan rana, an yi wa maza 43 na rundunar ado, yayin da rundunar ta sami fararen fata guda ɗaya da launuka biyar masu launi don ayyukanta. Rundunar Estonia ta yi yaƙi a Chashniki da
Smoliani. - Ka yi haƙuri. A watan Satumba an karfafa shi da rundunar ta 8 ("druzhina") na 'yan bindiga na Saint Petersburg.