Russian tsars before Peter maintained professional hereditary musketeer corps (streltsy in Russian) that were highly unreliable and undisciplined. In times of war the armed forces were augmented by peasants. Peter I formed the Imperial Russian Army built on the German model, but with a new aspect: officers not necessarily from nobility, as talented commoners were given promotions that eventually included a noble title at the attainment of an officer's rank. Conscription of peasants and townspeople was based on quota system, per settlement. Initially it was based on the number of households, later it was based on the population numbers.