It is said that no second heir to the British throne has been named John because of the reputation of the first.

King John (1199-1216) could be charming and efficient, but he was ruthless and utterly untrustworthy, and several times he drove his subjects to the point of rebellion. Out of one of those rebellions emerged the most influential constitutional document in Anglo-American history -- perhaps the most influential of all time.

On June 15, 1215 in the meadow of Runnymede on the banks of the River Thames, English barons forced John to seal the first version of Magna Carta. The Latin title reflects the document’s Medieval Latin text. It came to be called ​​Magna (great) to distinguish it from the lesser Charter of the Forest.

Thus the coming year of 2015 marks the 800th anniversary of the event at Runnymede.

John died in 1216, after having repudiated the Charter. However, his successors have repeatedly pledged their adherence to it. Portions remain law in England today.

In many respects, Magna Carta was similar to other medieval European royal charters granting liberties and privileges, and indeed it restated some terms from a charter issued by Henry I over a century earlier. What distinguished Magna Carta was the universality of its grants. It acknowledged rights and privileges not merely for the barons who extracted it, but also for women, for merchants, for the church, for all free persons, and in some cases even for unfree agricultural workers. A particularly striking provision (Chapter 60 of the 1215 version) provided that the barons would grant to their own vassals all the liberties the king was granting them.

This universality probably was due to the vision of Stephen Langton, Archbishop of Canterbury, a former professor at the University of Paris, and​ ​the inventor of our system of dividing biblical books into chapters. Langton played a major role in negotiating the settlement between John and the barons.

Subsequent English kings repeatedly reissued or reaffirmed Magna Carta, even if they did not always honor its terms. Copies were lodged in every county in England. Magna Carta became the first entry in the English Statutes at Large. It was read aloud to the populace on regular occasions in public places throughout the realm. During the reign of Edward III (1327-1377), Parliament enacted statutes elucidating the meaning of key provisions. By the close of the Middle Ages, Magna Carta was recognized as a document of constitutional proportions.

Parliamentary spokesmen relied on it during their pivotal struggles with the kings of the Stuart dynasty (1603-1689). The most famous of the Parliamentary spokesmen, Sir Edward Coke (1552-1634), penned a treatise on Magna Carta. This subsequently was included in his Institutes of the Lawes [sic] of England, the single most popular law treatise in Britain and in British America until supplanted by Blackstone in 1765. Coke was therefore a primary source from which the American Founders learned their law.

Magna Carta, particularly as interpreted by Coke, formed a basis for terms in key American governmental documents. Echoes or paraphrases appeared in each colony’s charter, in the Massachusetts Body of Liberties, in Pennsylvania’s Frame of Government, and in similar instruments. During the decade of tension with Britain that preceded the American Revolution, spokesmen for the American cause relied partly on Magna Carta to support their case. After independence, Americans inserted provisions derived from Magna Carta into their new state constitutions, into the Articles of Confederation, and into the federal Constitution of 1787.

The Due Process Clauses of the Fifth and Fourteenth Amendments are the successors of Magna Carta’s famous Chapter 39, which provided that the king would not penalize any subject other than according to the judgment of the subject’s peers or the law of the land. The Fifth Amendment’s Due Process clause included an implicit ban on many civil ex post facto laws, which served the goal of its drafter, James Madison, of compensating for the narrow ratification-era understanding of the Ex Post Facto Clauses (Art. I, sec. 9, cl. 3 & sec. 10, cl. 1).

The Constitution’s Privileges and Immunities Clause (Art. IV, sec. 2) stems from Magna Carta’s guarantees of free entry and exit from the kingdom for merchants and other travelers (Chapters 41 and 42). The proportionality rule of the Eighth Amendment derives, in part, from Magna Carta’s bans on excessive amercements and on seizure of the tools people used to earn a living.

Magna Carta contains predecessors of the Sixth Amendment guarantees of a local (Chapter 18) and speedy (Chapter 40) trial, and to confront witnesses (Chapter 38). The Thirteenth Amendment proscription against involuntary servitude is prefigured in Chapter 23; aspects of the Commerce Clause (Art. I, sec. 8, cl. 3) by Chapter 33, and the Weights and Measures Clause (Art. I, sec. 8, cl. 5) by Chapter 35. The Fifth Amendment Takings Clause is anticipated by Chapters 19 and 21 of the 1225 version.

No wonder Justices of the Supreme Court have cited Magna Carta in over 175 cases. It a foundation for American liberties -- as it has been a foundation of the liberties widely enjoyed throughout the modern Anglosphere.

Rob Natelson is Senior Fellow in Constitutional Jurisprudence at the Independence Institute in Denver. He wrote the entry for Magna Carta in the Encyclopedia of the Supreme Court of the United States (Macmillan Reference, 2008). Supreme Court justices have cited his work 16 times in four different cases since 2013.