The New Model Army was a military force established in 1645 during the English Civil War. It was created by the Parliamentarians to fight against the Royalists, who supported King Charles I. The army was known for its discipline, organization, and effectiveness, playing a crucial role in the eventual defeat of the Royalist forces. Led by notable figures such as Oliver Cromwell, the New Model Army introduced innovative military strategies and promoted merit-based promotions. Its success contributed to the establishment of the Commonwealth of England, marking a significant shift in the country's governance and military structure.