In 1861 Grujić was in Prussia studying at the Military Academy when an uprising broke out in the Russian sector of partitioned Poland, the Polish uprising opposed young Polish insurrectionists to Russian occupiers, inspired by romantic and revolutionary nationalism that was sweeping across Europe at the time, Sava Grujić travels to Poland and joins the rebellion. Grujić fought alongside fellow Serbian volunteer Jevrem Marković another graduate from the Belgrade Military Academy who had also been sent to Prussia to study (training as a cavalry officer). After the failure of the Uprising, Grujić returned to St. Petersburg and is allowed to return to his studies while Jevrem Marković returns to Belgrade