Which pivotal document was signed in 1215, limiting the powers of the English king?

The Magna Carta, signed in 1215, is a cornerstone of constitutional law and a significant milestone in the development of limited government. This document was created as a result of the conflict between King John of England and a group of rebellious barons who sought to protect their own rights and limit the king's arbitrary power.

The Magna Carta established the principle that everyone, including the king, was subject to the law. It included provisions that safeguarded certain rights, such as the right to a fair trial and protection from unlawful imprisonment, which would later influence many democratic systems around the world. This document laid the groundwork for the development of constitutional democracy and highlighted the idea that rulers should not have absolute control, which was revolutionary for its time.

In contrast, the other options were enacted in different contexts and centuries. The English Bill of Rights was established in 1689 as a response to the Glorious Revolution, the Petition of Right was introduced in 1628 to address specific grievances against King Charles I, and the Commonwealth Act came into being after the English Civil War in the 17th century. These documents focus on specific issues or governance during their times, but none share the foundational impact on limiting monarchical power that the Magna Carta represents.