The Low Middle Ages

Hollywood Historians like to lump all of the Middle Ages into one indistinct era, but a study of real history will show that the period of the fall of Rome and the rise of Monasticism in Europe was more of a prelude to the true Middle Ages. It began with an alleged dark age, when people were supposedly too busy staying alive to write histories, had a few peaceful years in the middle, and ended with Vikings ravaging the coasts, and horsemen storming out of the east. In reality, there were substantial intellectual and cultural advancements during the alleged "Dark Ages," and modern historians universally reject classifying the Early Middle Ages as being an "age of darkness."

Most Hollywood monks are pious men with tonsures, clad in long black robes. They frequently spend all their days dipping feathered pens into inkwells and scribbling strange uncials into large books by candlelight. If they're being played by Derek Jacobi, they may take time out of their busy schedule of scribbling, praying, singing, and rejecting all of their worldly goods to mill about the town and solve a murder mystery or two...

If not a monk, the Hollywood European of this time is generally either a cruel warlord pursuing his droit-de-seigneur or an oppressed peasant.

Or he is a barbarian invader. For this is also the time of the Vikings, hearty sailors in horned helmets who loved burning down monasteries and carrying off struggling peasant women, while Alfred the Great burnt cakes.

Other vaguely remembered names from this period are Canute, trying to turn back the tide, and Charlemagne.

The arrival of the Normans in 1066 is as good a cut-off point as any, especially since they were the ones who really started building castles with a vengeance. After that, see The High Middle Ages.

Tropes Associated with this era include

 * An Axe to Grind (probably the most frequent non-spear weapon, as an axe is fairly easy for a relatively unskilled smith to make, and peasants tended to have these around anyway for firewood)
 * Ancestral Weapon (often Truth in Television, as the difficulties of making steel and pattern welding made high-quality blades expensive, and they tended to get passed down, some eventually receiving a name and a legendary Backstory.)
 * Barbarian Hero
 * Blade on a Stick (What most fighters actually had to settle for, when they weren't stuck with farming implements or just the stick)
 * Drop the Hammer
 * The Dung Ages
 * Here There Were Dragons
 * Heroic Fantasy
 * Historical Domain Character, though, except for King Arthur (and possibly Attila the Hun or Alfred the Great), most people will never have heard of them. (Gunthaharius of Burgundy is not exactly a household name.)
 * Horny Vikings
 * Just Before the End, for Rome
 * King Arthur
 * Knight in Shining Armor (historically inaccurate though it is: "warlord in rusty chainmail" was the best they had then. Knighthood as we picture it didn't exist yet)
 * Medieval Morons
 * Norse Mythology
 * Swiss Army Weapon (inverted-- most Dark Agers carried one big knife that they used for everything from cutting food to carving wood to killing. Hopefully with a cleaning of some kind in between-- you wouldn't want to get foodstains on your dead enemy, after all)
 * The Time of Myths

Anime and Manga

 * Vinland Saga, set right towards the end of the dark ages.

Film

 * Monty Python and the Holy Grail
 * Note that in the DVD commentary, the Pythons admit that Anachronism Stew is at work: It is said to be set in Dark Ages Britain, but the costumes are based on fashions from the 1300s.
 * For that matter, nearly all the many movie and literary versions of King Arthur
 * The 13th Warrior
 * The Vikings (1958)
 * The War Lord (1965)

Literature

 * The Nibelungenlied and its derivatives, such as Richard Wagner's The Ring of the Nibelung and Fritz Lang's Die Nibelungen : Siegfried and Kriemhilds Rache
 * Beowulf and its derivatives, such as Beowulf and Grendel (2005) and Beowulf (2007)
 * The King Arthur romances
 * The Song of Roland, Orlando Innamorato and Orlando Furioso
 * G. K. Chesterton's The Ballad of the White Horse
 * Brother Cadfael
 * Enchantment by Orson Scott Card
 * JRR Tolkien's Farmer Giles of Ham
 * Sea of Trolls and Land Of The Silver Apples
 * Many of The Icelandic Sagas, specifically the Sagas of Icelanders (semi-historical, halfway realistic stories set c. 900-1030 AD) and the Legendary Sagas (heroic legends set in a mythic Dark Age Europe, faintly echoing real-life history from c. 400-900 AD). For example:
 * Ragnar Lodbrok and His Sons, set in a fictionalized 9th century.
 * Heimskringla, a medieval history of Norway spanning from the Time of Myths to the High Middle Ages.
 * Saga of the Jomsvikings, semi-historical adventure set in the 10th century.

Live-Action TV

 * Roar
 * Cadfael

Newspaper Comics

 * Hagar the Horrible
 * Hal Foster's Prince Valiant in the Days of King Arthur (and the derivative movie and cartoon), which features both the good and the bad kind of Horny Vikings)

Theatre

 * Richard Wagner's Lohengrin and Parsifal, though both are more often staged as if they took place in The High Middle Ages.