The New Model Army consisted on paper of 22,000 soldiers, comprising eleven regiments of cavalry each of 600 men for a total of 6,600, twelve regiments of infantry each of 1,200 men for a total of 14,400, and one regiment of 1,000 dragoons. Units from the existing Parliamentarian armies of the Earl of Essex, the Southern Association under Sir William Waller and the Eastern Association under the Earl of Manchester were reassigned to provide regiments for the new army. Although the cavalry regiments were already well up to strength and there was no shortage of volunteers, the regiments of foot soldiers needed 7,000 reinforcements to be brought up to full strength. Men were impressed from Parliamentarian-held areas in the South and East to provide the necessary drafts, but many of these soon deserted and the Army was still 4,000 men short of its paper infantry establishment in May 1645.