The English king during the signing of the Magna Carta in 1215 was King John. His reign was characterized by heavy taxation, military failures, and conflicts with the nobility, which ultimately led to widespread discontent. The Magna Carta, or "Great Charter," was created as a result of the barons' revolt against King John's authoritative rule. It established the principle that the monarchy was subject to the law and laid the groundwork for constitutional governance. The Magna Carta is considered a foundational document in the development of modern democracy, influencing legal systems and concepts of individual rights in subsequent centuries.