If you head just south of the Shrine to Peryite, only a small journey west of Karthwasten, North-North East of the Lover Stone, you will come across a skeleton (about halfway up the mountain). If you look just to the side of the skeleton you will see a sabre cat stuck between two rocks with a glass sword through its mouth and head. This is a reference to the scene in 300 where Leonidas leads a wolf to a narrow passage then stabs it through the mouth with a spear.
Combining the title of the book "Troll Slaying" with the author's name, makes the word Finn-Troll, the same name as that of the Finnish folk metal band Finntroll. Many Finntroll songs contain lyrics involving the fighting of trolls also. A copy can be found in the bookcase of Farengar Secret-Fire at Dragonsreach in Whiterun.
Game of Thrones
When you complete No One Escapes Cidhna Mine in the favor of Thonar Silver-Blood, he apologized and gives you his family ring, saying that the Silver-Bloods pay their debts. This may be a reference to the unofficial motto of the Lannister house.
Ghostbusters 2
In the Soul Cairn, the player can find a soul that says "Death is but a door, time is but a window: I'll be back." These were the last words of Vigo the Carpathian, the main antagonist of the film Ghostbusters 2'.
At night along roads you have a chance of encountering a spectral horseman
The Headless Horseman
without a head galloping along at full tilt. He carries an axe on his back, which is likely a reference to Washington Irving's "The Legend of Sleepy Hollow". If you follow him, he eventually takes you to Hamvir's Rest, where there are several skeletons to fight and a Master chest.
Katatonia
During the quest Darkness Returns in the Pilgrim's Path while returning the Skeleton key, a book titled "Nydstrom's Diary" is found, Nydstrom being the guitarist from prominent Swedish progressive metal band Katatonia. It contains several references to the band's music including "Night is the New Day" from their latest album and "Ghost of the Sun," a song from another album.
The Legend of King Arthur
If you have found Broken Tower Redoubt, directly south of it there will be a place called Rebel's Cairn where you will find a pile of stones in the front of the cave and there will be a Steel Sword in the top stone, which is a reference to the sword in the stone in the legend of King Arthur.
Excalibur?
Slightly Northeast of Bleakwind Basin, there is a pond with a skeletal arm holding a leveled sword, which is a reference to the Lady in the Lake in the legend of King Arthur.
The Lady Stone is found in the middle of a lake, another reference to the Lady in the Lake.
Lord of the Rings
In Whiterun, the giant tree there is called the Gildergreen. It is grown from the Eldergleam, the oldest living thing in Skyrim, but it is dying. This is similar to the Gondorian capital of Minas Tirith in Lord of the Rings: Return of the King, where the legendary White Tree faces a similar fate.
In Whiterun, during Battle for Whiterun,Hadvar or Ralof can be seen near the city wall after the battle. Whichever one is present makes a reference to Legolas and Gimli's ongoing competition in the movies: "I'm pretty sure I killed more than you. I was counting."
The city of Whiterun greatly resembles Edoras, the capital of Rohan; both cities are built atop a bluff, with the palace at the top of the hill.
During "A Night to Remember" one of the tasks is to obtain a wedding ring from a hagraven named Moira who will say "My precious" while trying to get the ring from her, in reference to Gollum.
When joining the Companions, Vilkas and Kodlak discuss the player's worthiness. Kodlak comments "What matters is their heart." to which Vilkas responds "And their arm". This is likely an intentional reference to the exchange between Eowyn and Eomer in Return of the King over Merry going to battle with the Rohirrim, in which Eomer comments "It is not his heart that I doubt, only the reach of his arm."
Minecraft
The Notched Pickaxe is a reference to "Notch", the creator of Minecraft. As a pickaxe it is used for mining and it features an enchantment that boosts Smithing, Skyrim's method of crafting. It is located just below the very top of The Throat of the World. Climb your way up the remaining part of the mountain by jumping and you should arrive there. There are a few ore veins there and the pickaxe itself will be embedded on a rock.
Pac-Man
In Endon's House in Markarth, look for a shelf in the back of the room with Sliced Goat Cheese, a row of Garlic and some Glow Dust arranged to look like a scene from Pac-Man.
The Pied Piper
The Dampened Spirits quest involves killing Hamelyn. His name, as well as his journal, both describe events similar to those in the myth, Pied Piper.
Snow White and the Seven Dwarves
Inside Blackreach you will find a building called the War Quarters. Inside these quarters, you'll find one room with 7 small beds, placed in a circle around a lantern. This may be a reference to Snow White and the Seven Dwarves. Opposite of the bedroom is a hallway and at the end another bedroom, where a much larger double-bed is found.
Star Trek
In the village of Ivarstead, there is a woman named Temba Wide-Arm. This is a reference to the Star Trek: The Next Generation episode Darmok, where one of the often-repeated phrases is "Temba, his arms wide."
This marks the second time Bethesda has put this Easter Egg in an Elder Scrolls game. A similar cave existed in Bloodmoon called Bjorn, referencing exactly the same scene of exactly the same movie in exactly the same manner.
If you travel with the ghost of Lucien Lachance he will some times say "I feel a disturbance in the void" which is very similar to the phrase "I feel a disturbance in the force" from the Star Wars movies which is often mentioned by Jedi.
Inside of Frostfruit Inn Erik can be heard talking to his father, with his father telling him "all I ask is that you stay on for one more season" and "that's just your mother's side in you." This is in reference to Uncle Owen's conversation with Luke in Star Wars Episode IV: A New Hope. Also, Calcelmo can be heard telling his nephew, Aicantar "Next season for sure".
Three Billy Goats Gruff
On your way to Hag Rock Redoubt, there is a bridge with a dead Troll underneath. If it's your first time visiting, you will witness two goats meeting a third at the end of the bridge then running off together. This is a reference to the child's tale, "Three Billy Goats Gruff," where a troll is defeated by a trio of goats. A similar reference was made in Oblivion, as well as this, there can be dead goats in caves where trolls are, which could further extend this reference.
A mammoth can be found directly east of Frostflow Lighthouse, frozen into the side of a glacier with arrows and what appear to be prehistoric spears embedded in its hide. The arrows in the mammoth appear to be Dwarven, hinting that the Dwemer may have killed this beast. This a Reference to a Mammoth frozen in ice and recovered in the 1990s.
High Hrothgar is obviously named after Hrothgar, the real life king of Denmark who was also a character in the epic poem Beowulf. The name may be a combination of his own name and that of his meadhall, High Herot.
Mercer Frey says "The die is cast" before he engages the Dovahkiin in combat during the quest Blindsighted. This is a reference to Julius Caesar's quote when he crossed the Rubicon and started a civil war.
The guard's frequent comments regarding "taking arrows in the knee" may be a subtle reference to the fact that Greaves are not an armor type in Skyrim, unlike in previous games, where Greaves protected the shin and knees.
In addition, a former Stormcloak soldier called Angrenor Once-Honored can be found in Windhelm who, when spoken to, says "I was one of the best soldiers the Stormcloak army had, but then I took a sword through the chest".
M'aiq reappears in Skyrim. He appeared in Morrowind and Oblivion, as an Easter Egg Basket of sorts for developers to comment on some of the game features that were removed, added, or were/are planned for the series as well as other RPG gaming community related remarks.
Labyrinthian was first introduced in Arena. Like in Arena, a magical guild (Mages Guild in Arena) is involved in your visit to Labyrinthian. And like in Arena, the player is going there to retrieve a magical staff (in Arena, you went to recover a piece of the broken Staff of Chaos).
A quest for the Companions involves killing Glenmoril Witches to cure Lycanthropy. Glenmoril Witches, and their relation to lycanthropy's cure were first introduced in Daggerfall.
During the quest The Cure for Madness in the ice cave portion of the quest, you encounter a unique troll named Udefrykte which is a reference to The Udyrfrykte from Bloodmoon who bears a similar appearance and is also found in a similar location though their names are spelled slightly different. The Udyrfrykte in turn is a reference to Grendel in the epic Beowulf.
The artifact Keening from the main quest of Morrowind makes a return. Unlike in Morrowind, Keening can be used without Wraithguard with no ill effects.
A drug called Balmora Blue figures in a Thieves Guild quest, named after the town of Balmora from Morrowind.
If you fail a persuasion check when first encountering Nelacar in the Azura's Star quest, he says "Right, now tell me the one about the Argonian maid and the lusty baron." This is a reference to the book from The Elder Scrolls series: The Lusty Argonian Maid. The same book exists in Skyrim, easily missed on a bookshelf amid burned and ruined books as well as found in Haelga's room in Haelga's Barracks in Riften. There is also another part of The Lusty Argonian Maid that can be read in-game.
A bar in the Grey Quarters of Windhelm is called New Gnisis Cornerclub named after Gnisis from Morrowind, and the habit of the Dunmer to call taverns "Corner Clubs". Local Nords will remark on the latter. Incidentally, Gnisis did not have a Corner Club.
In Dragonborn, a Bosmer wizard can be seen as random encounter on Solstheim. This wizard will cast a flying spell when approached, but soon falls out of the sky and dies upon impact. This is likely a reference to Tarhiel.
Lucien Lachance returns in Ghost form when you obtain the power "Summon Spectral Assassin".
Lucien will make several references to Oblivion's plot, especially to the Dark Brotherhood quests of Oblivion. These include mentioning the death of Uriel Septim VII, the story of Mathieu Bellamont and mentions of performing a "purification" on a Dark Brotherhood sanctuary, which includes how he is "more partial to apples" than the poison stew during the quest "To Kill An Empire".
One of the employers for the Dark Brotherhood is named Amaund Motierre. Francois Motierre hired the Dark Brotherhood in Oblivion. Gabriella will remark that the Motierres are a powerful, old family of Bretons on Cyrodill. Both Motierres' missions involve a trip through a zombie-filled crypt.
Upon finding a Crimson Nirnroot, a quest starts named, "A Return To Your Roots" which is a reference to Oblivion 's Nirnroot quest. Sinderion, the Altmer who was after Nirnroot in Oblivion, can be found by a Crimson Nirnroot, however he is dead and nothing but bones.
If you help Ralof escape Helgen, you will arrive at Riverwood and his sister will say "Any friend of Ralof's is a friend of mine". This is a reference to "Any friend of Martin's is a friend of mine", the way NPC's greet you in Oblivion after completing the main quest.
The husk of a giant mudcrab can be found within the plains surrounding Whiterun, continuing the giant mudcrab tradition from previous games. It is however, very much dead upon discovery, unlike in Oblivion, where the giant mudcrab is alive and fightable. However, there is a quest where you have to fight the Guardian Mudcrab Spirit at that location.
In the Dark Brotherhood, if you read Cicero's Journal Volume 1, he writes; 27th of Rain's Hand, 4E 187 Completed the Arena contract. I ultimately decided to pose as a starstruck fan, and immediately got into the Grand Champion's good graces. While escorting the arrogant fool through the Great Forest, I slashed his throat and left the corpse for the bears. This is a reference to the Adoring Fan in Oblivion, who many gamers found incredibly annoying.
Shadowmere, the horse given to you in Oblivion by Lucien Lachance, is again given to you by Astrid during the Dark Brotherhood quests. If you have the spell "Summon Spectral Assassin" cast and Lucien is following you as a spectre, as he approaches Shadowmere he will say "Shadowmere, my old and dear friend."
When asking Elgrim about his store, he mentions that it is hard to get Painted Troll Fat, an ingredient from Oblivion, only acquirable by painted trolls from the quest A Brush With Death. You may also overhear him scolding Ingun Black-Briar for wasting his supply of the aforementioned ingredient.
In Riften, you can find a Dark Elf named Romlyn Dreth working for the Black-Briar's mead production, who is related to Valen Dreth, the Dark Elf prisoner in Oblivion who taunts the player character at the beginning of the game. At night, in the Bee and Barb, you can hear Romlyn tell fake stories about Valen and the Oblivion Crisis (example being how Valen single handedly killed 6 Imperial Guards before he was taken to jail.)
The quest Laid to Rest features a Vampire named Movarth. Movarth's story features in the book Immortal Blood, which first appeared in Oblivion and can still be found in Skyrim.
The smuggling/pirate ship Red Wave in Solitude harbor draws its name from the Redwave, an enchanted cutlass (Pirate's Sword) found in Oblivion as a quest reward to The Ghost Ship of Anvil. Further references ties the two: A book found in Oblivion revealed that a Dark Brotherhood Assassin was responsible for killing everyone on board the titular ship. While in Skyrim, a Dark Brotherhood Quest (Contract: Kill Safia) takes place on the Red Wave.
There is a small island made of ice to the north east of The Tower Stone that has a constant slope upwards and is unmarkable on the map, but is shown on it. At the very top of this iceberg there is a frozen skeleton with a flag planted in the ground with a chest containing loot and a book called The Knights of the Nine that details the history of The Knights of the Nine, thus suggesting that the dead body was a member of this faction from the DLCKnights of the Nine for Oblivion.
Inside Riften's Keep, in the court mage's room, a letter behind the counter can be found, called
Note's Location
"Per Your Requests". It is a response to a letter sent to Wylandriah, a female Bosmer, regarding the nonexistence of a bunch of items that the mage asked for. One of the items is the infamous drug from the Isles called "Greenmote". Mirabelle assumes that Wylandriah has made a mistake, writing that Greenmote does not exist and that she miswrote "Greenspore".
Sheogorath has the same voice as his predecessor from Shivering Isles. He also makes references to Passwall and Haskill. He also refers to the plot of Shivering Isles when introducing himself, saying Sheogorath is a title that gets passed "From me to myself."
A running joke in Bethesda games (dating all the way back to Arena, and present in other Bethesda games such as the Fallout series) about sweetrolls can be found throughout the game.
The Sweetroll can be found throughout Skyrim as a normal food item, and is sometimes placed in strange locations.
While following you, Cicero will sometimes say, "Cicero is hungry, need a sweetroll...or a carrot."
Children can rarely be heard saying, "Give me back my sweetroll!" while chasing each other around.
The Wabbajack can sometimes place a sweetroll behind the enemy, causing them to turn around. Rarely, it may actually turn an enemy into a sweetroll.
The Jarl of Whiterun's daughter can be heard complaining that it is almost impossible to find a decent sweetroll in Whiterun.
Having your sweetroll stolen was first mentioned in Arena when answering moral questions to determine your class. It was used in a similar context in Daggerfall and Morrowind.
M'aiq the Liar comments that he once tried dual-casting spells and burnt his sweetroll.
Inside the Quicksilver Mine located at Dawnstar, you'll find a sweetroll on a table near the back of the mine. If you pick it up and Edith, who also works at the mine, spots you, she may exclaim, "Well, somebody had to take it!"
