Some thoughts about some things which happened 800 years ago.
The first which comes to my mind associated with 1215 is the Magna Carta. As you may know, "magna carta" is Latin for "great charter." Some people call it "Magna Carta" instead of "the Magna Carta." I don't care whether you call it one or the other. But some people might.
I honestly don't know what to make of the Magna Carta. Some barons were in rebellion against King John of England in 1215. They, the barons, had the document drawn up which is known as the Magna Carta, which granted some rights to the barons, John very unwillingly put his seal on it on June 15, which is why there are going to be big celebrations here and there this coming June 15. On June 19 the charter officially went into effect, but in August John rejected it, which led to all-out war between him and some barons. Also in August Pope Innocent III declared the Magna Carta to be invalid. In 1216 John died, and his son and heir King Henry III re-issued the charter, but with some restrictions, hoping that this would end the war. But the barons wouldn't agree to the restricted charter and the war dragged on.
Out if this particularly dismal beginning the Magna Carta somehow became a great symbol of the rights of all English people. Another version was issued in 1217, and another in 1225, and eventually every English monarch upon taking the throne would ceremoniously renew the charter. The members of the English Parliament, and then its successor the British Parliament, have often claimed that the Magna Carta was the founding of Parliament, although actually a Paliament already existed going back to William the Conqueror, and although a Parliament even faintly resembling the modern one didn't begin to take shape until long after 1215. The rebels in the American Revolution referred to the Magna Carta as embodying the rights for which they were fighting. Which all goes to show that a lot of English and American people haven't been able to read Latin.
Be that as it may, symbols do have power even when they're misunderstood, or perhaps especially when they're misunderstood.
In 1215 the 4th Lateran Council began. The proceedings of this famous Council are so horrible and depressing that I'm just going to ignore them altogether, and instead say a little about the Lateran Palace in Rome where the Council took place, and from which it gets its name. The Palace is named after the Laterani family, who owned it from some time which is misty from distance even by the standards of Rome, until it was confiscated by the Emperor Nero, who accused the Consul-designate Plautius Lateranus of plotting against him. Constantine the Great built a church on the site and gave it to the Bishop of Rome at some time which is not precisely known. For most of the time from the 4th century onwards, the the Lateran Palace was the primary residence of the Popes, until the late 16th century, when they moved to the Vatican. The Lateran Palace is about 2 miles from the walls of Vatican City, but it is one of the few possessions of the Vatican outside the walls. Today it houses a museum open to the public, dedicated to the history of the Papal States, as well as the residence and offices of a Cardinal.
In 1215 the armies of Genghis Khan set fire to Beijing. The fire was not put out for over a month.
In 1215 the game of chess was known all over the Islamic and Christian parts of the world.
In 1215 Matthew Paris turned 15 years old. As an adult he would write some of the best historical works made in Medieval Europe, and very impressively illustrate his manuscripts. Despite his name, Paris was thoroughly English. Did he hear about the Magna Carta as early as 1215? If so, I wonder what he made of it.
In 1215 Saxo Grammaticus had either recently finished or was about to finish his great work, the Gesta Danorum, a story of the Danish people modeled after Vergil's Aeneid, which is modeled after Homer's Iliad and Odyssey.