Detail of the Bayeux Tapestry showing the slaying of Harold II

Detail of the Bayeux Tapestry showing the slaying of Harold II, England’s last Anglo-Saxon king. The embroidered words read (in Latin) “Harold rex interfectus est” (Harold the king is killed).

October 14 marks the anniversary of the Battle of Hastings, the bloody fight that sealed the deal on the Norman Conquest. In case your history is a little rusty, the Norman Conquest was the takeover of England in 1066 by invaders from northern France led by William I, better known as William the Conqueror.

William’s capture of the English crown from Harold II was a turning point for history, politics, literature, and art—but also for language. It began the transformation of English from an orderly Germanic tongue into the sprawling, messy hybrid we speak today. In short, the Battle of Hastings is the reason we talk funny.

After the Conquest, Saxon aristocrats were killed or driven off their lands, which were handed over to Norman barons. While 90+ percent of the population—the peasants—continued to speak English, their fancy new lords spoke French. For 300 years after the Battle of Hastings, French was the language of England’s kings and courtiers, landowners and officials. Latin was also a major player, serving as the language of diplomacy, philosophy, and theology. Where written language was concerned, English came in a distant third.

This helps explain why most manuscripts created in England after the Norman Conquest, such as the St. Albans Psalter (which was featured in the exhibition Canterbury and St. Albans: Treasures from Church and Cloister), are written not in English, but in French and Latin.

Scenes from the Life of Saint Alexis in the St. Albans Psalter / Alexis Master

Scenes from the Life of Saint Alexis in the St. Albans Psalter, about 1130, Alexis Master. Tempera and gold on parchment, 12 3/16 x 8 5/8 in. Dombibliothek Hildesheim. The writing is in French.

The influence wasn’t all one way, of course. While the English “were adopting French as a language of refinement and prestige,” said Geoff Rector, a scholar of medieval literature, “the Normans were adopting the literary traditions of the English—writing histories, saints’ lives, and biblical translations in French.”

Precisely because French was the language of prestige and power, it’s no surprise that the Saxons soaked up some 10,000 loans: air, beauty, color, feast, flower, soil, story. Many of the new words reflect the elite status of the Normans: duke, countess, noble, baron, throne. Also notably: servant.

In most cases, these Frenchy words were ones English speakers already had perfectly good names for. The Saxons had a word for “wood thing you sit on,” but the French chaiere came in anyway, joining our native word for chair, stol, which eventually became stool. Have you ever wondered why veal isn’t just called calf, or why we say mutton instead of “sheepsmeat”? Simple: the words for the foods come from Old French, while the words for the animals (tended by Saxon rustics) stem from Old English.

At its core English remained a Germanic language, a close sibling to the dialects that would evolve into modern sister languages such as German, Dutch, and Danish. But in its vocabulary, it became a multi-headed hybrid. By 1400, in fact, about one in five words in English were of French origin.

This medieval franglais also primed Middle and Modern English to soak up yet more words from French, and from hundreds of other languages, a trend that continues to this day. It’s this shameless borrowing that gives English such a surfeit of evocative synonyms: cease and stop, battle and fight, feeling and emotion. English is still characterized by great openness to the new—we’ll take a good word any way we can borrow, steal, or invent it.

Today, only about a third of the words on an average book page go back to Old English, the tongue of King Harold who died on October 14, 1066. Purists like to complain about foreign and made-up words polluting “correct” English, but it’s been happening since the language came on the scene 1,500 years ago. So in a way, we have the Norman Conquest to thank for squee, selfie, srsly, and all the other fabulous, crazy new words that keep English vibrant and alive.