Edward Montagu, 2nd Earl of Manchester, KG, KB, FRS was an important commander of Parliamentary forces in the First English Civil War, and for a time Oliver Cromwell's superior.

Robert Devereux, 3rd Earl of Essex, KB, PC was an English Parliamentarian and soldier during the first half of the 17th century. With the start of the Civil War in 1642, he became the first Captain-General and Chief Commander of the Parliamentarian army, also known as the Roundheads. However, he was unable and unwilling to score a decisive blow against the Royalist army of King Charles I. He was eventually overshadowed by the ascendancy of Oliver Cromwell and Thomas Fairfax, and resigned his commission in 1646.