With the decay of theJanissaries over the years, a sort of "national guard," known as the Yamaks (assistants), was established by the Ottoman Empire to provide extra manpower for the force.

Affiliated to the Janissary Ortas in times of peace, this force consisted of large numbers of unpaid men, primarily local artisans drawn from the towns in which the various Ortas were headquartered. In times of war, these men would be formally enrolled in their parent Orta under itinerant officers.

The arrangement was attractive both to the Janissaries and to the men so affiliated. While not paid in times of peace, the Yamaks were allowed to wear the emblem of their Orta tattooed on their arms and legs. This made them, like regular Janissaries, immune from punishment by civil authorities and exempt from taxation. They could also use the influence of their Orta and the personal contacts they thus made for their own business ends.

The Janissaries, for their part, acquired an enormous reserve force, which not only was a blessing in time of war, but could also be used to help them impose their will on the community and on Ottoman officials in times of peace.

The idea also originally appealed to the Ottoman state. But while the idea may have seemed an easy, cost-effective way to enlarge the army on paper, in reality it was a disaster. The Yamaks invariably proved to be very poor soldiers and very active reactionaries.

Contrary to most published reports, it was the abuses of the local Yamaks, and not the Janissaries, which sparked the Serbian revolt in 1804, and it was a revolt by the Yamaks in Istanbul in 1807 which sparked the revolt, which was only later joined by the Janissaries, that led to the overthrow of Sultan Selim III.