Prior to Peter I, the bulk of the military was formed from the nobility and people who owned land on condition of service. During wars additional recruiting of volunteers and ordinary citizens was common. Peter I introduced a regular army consisting of the nobility and recruits, including conscripts. The conscripts to the Imperial Russian Army were called "recruits" in Russia (not to be confused with voluntary recruitment, which did not appear until the early 20th century). The system was called "recruit obligation" ().