Nobility

Kings

 * The Alligator King
 * King Derwin
 * The Elvises call themselves "the King"
 * Ernie imagined himself as a king in Ernie Is King, and once played Old King Cole on Sesame Street. He also appears as a caveperson king in a sketch which was adapted into a book.
 * King Fred Charming
 * King Goodheart
 * King Goshposh
 * Grover once played the King of Siam on "Monsterpiece Theater"
 * Gunge, and later Philo, are hailed as the lost king of the Doozers in "Gunge the Great and Glorious"
 * The Hypocritic Oaf played a king on The Jim Henson Hour
 * Jareth, the Goblin King
 * Kermit the Frog as King Midas and the "Rumpelstiltskin" king in Muppet Classic Theater
 * Kermit as the King of Spades, Hearts, Clubs and Diamonds in a deck of playing cards
 * Kermit, Prince of Denmark
 * The King
 * King of 8
 * The King of Id
 * The King of Phumph
 * Link Hogthrob as the King of Hearts in The Muppet Show Episode 506
 * King Peter the Persnickety
 * King Ploobis
 * King Rupert the First
 * King Rupert the Second
 * The Monkey King
 * Pa Gorg
 * Rowlf as the king in the jousting scene from episode 305 of The Muppet Show

Emperors

 * Anything Monsters as First Emperor and Last Emperor on Sesame Street
 * The Emperor of Lilliput in Gulliver's Travels
 * Fozzie Bear as the Emperor in Muppet Classic Theater
 * Skeksis Emperor
 * Moo-Ing, emperor of Lactosia

Queens

 * Aunt Myrtle
 * Queen Esmerelda
 * Ma Gorg
 * Queen Peuta
 * Miss Piggy as Cleopatra in The Muppet Show Episode 409
 * Miss Piggy as the Queen of Hearts in The Muppet Show Episode 506
 * Miss Piggy as Queen Midas in Muppet Classic Theater
 * Piggy as the Queen of Spades, Hearts, Clubs and Diamonds in a deck of playing cards
 * Pearl Bailey as Queen Guenevere on The Muppet Show in Episode 305
 * The Queen
 * The Queen of Arabia
 * The Queen of Phumph
 * Queen of 6
 * Queen of Trash
 * Queen Quinella
 * The Yellow Queen from Sleeping Birdie
 * Pearl Bailey as Queen Guenevere in the jousting scene from episode 305 of The Muppet Show

Princes

 * Junior Gorg
 * The Artist Formerly Known as Prince guest-starred on Muppets Tonight
 * Prince Arthur Charming
 * Prince Charming
 * Prince Firstly
 * Prince Leo in The Heartless Giant from The StoryTeller
 * The Prince of Phumph
 * Prince the Dog
 * Sir Robin the Brave

Princesses

 * Princess Azalia
 * Princess Charming in CinderElmo
 * Daffodil
 * Princess Gwendolinda
 * Princess Lulabelle
 * Princess Melora
 * Princess Penelope
 * Miss Piggy as Princess Leia from Star Wars in Episode 417

Miscellaneous Sovereigns

 * Dominar Rygel XVI
 * The Swedish Chef as the Caliph in The Muppet Show Episode 518
 * The Tsar of Russia in "The Soldier and Death"

Aristocracy

 * Baron Purpura
 * Baron Von Rottweiler
 * Count von Count
 * Countess Dahling von Dahling
 * Countess von Backwards
 * The Duchess
 * Duke of York
 * Elmo as "Lord Elmo" in A New Baby in My House
 * Lady Holiday
 * Lady Two
 * Lord Chatterly
 * Lord Hog

Knights

 * Sir Arthur Conan Rubberducque
 * Sir Blunderbrain
 * Sir David Tushingham
 * Sir Didymus
 * Ernie imagines that he is Sir Ernie in the song "Imagine That."
 * Sir Linit

Real World Nobility

 * Princess Anne
 * Sir Bob Hope
 * Sir Derek Jacobi
 * Sir Elton John
 * Sir John Gielgud
 * Sir Michael Caine
 * Sir Michael Hordern
 * Sir Peter Ustinov
 * Sir Roger Moore
 * Sir Spike Milligan
 * Dame Cleo Laine
 * Dame Helen Mirren
 * Dame Julie Andrews
 * Dame Shirley Bassey
 * Lord Lew Grade