Why did Cromwell dissolve the first Protectorate parliament?

Early-to-mid-17th-century Britain was marked by ongoing struggles between the monarchy and Parliament, and between Puritanism and Anglicanism. This led to two civil wars, in 1642–1645 and 1648–1649. Ultimately, King Charles I's armies were defeated, and Charles I was tried by Parliament for high treason and executed.

After Charles's death, England was declared a commonwealth, and Oliver Cromwell, a member of Parliament and a Puritan who had risen rapidly through the ranks to become the Parliamentary army's commander, became the Lord Protector of England, Scotland, and Ireland. Cromwell's Protectorate lasted from 1653 to 1659.

After Cromwell assumed his new position, he called together the first Protectorate Parliament, which he expected to focus on "healing and settling" following the turmoil and strife of civil war. However, those pushing a more radical agenda of constitutional reform quickly dominated Parliament. Recognizing that Parliament would not deal with the issues that he thought were most important, Cromwell dissolved the first Protectorate Parliament in January 1655.

For five years, Cromwell ruled essentially as a military dictator. After his death in 1658, his son Richard became the Lord Protector. But because he had no power base in the Parliament, he was forced to resign in 1659, ending the Protectorate.

Parliament soon restored the monarchy, with Charles II as king. Cromwell's body was exhumed in 1661, he was posthumously executed, and his head was removed and displayed on a pike outside Westminster Hall until 1685.