King Bob the Nth

Often, if a work wants to portray a decaying or at least very old kingdom with entrenched rulers, they will have a leader who has a number, after their name (Eg. King Bob IX). These are always written in Roman numerals and the large ones can actually be Truth in Television: France, for example, had 18 King Louis.

Comic Books

 * The ruler of Syldavia in the Tintin (Comic Book) story King Ottokar's Sceptre was King Muskar XII.

Fan Fic

 * Played straight in the Gene Catlow fanfic The Basalt City Chronicles, in which Priest-Emperor Zaykar Kh'Naral is the 24th of that name. His grandfather was Rraghan Kh'Naral CDLXVII (The 467th). It's said that their dynasty reaches back into prehistoric times.

Literature

 * Pteppic in the Discworld book Pyramids is Pteppicymon XXVIII when he takes the throne (however briefly). That's a reference to the Real Life pharaohs of Egypt; the last pharaoh was Ptolemy XV, Caesar's son by Cleopatra. But the Ptolemies ruled only in the Ptolemaic Dynasty, which lasted about 250 years (and not all the Ptolemaic pharaohs were named Ptolemy!); before the Ptolemies were more than thirty-five previous dynasties and interstitial rules, dating back no less than three thousand years. And that's an incomplete list.
 * Elric of Melnibone is the eighth monarch to bear that name, and the 428th Emperor of Melnibone. His father was Sadric LXXXVI.
 * Melnibone did last over ten thousand years, after all.
 * Dune makes a good example. It's the year 10,191 of the Galactic Empire, and the current monarch is Shaddam IV, 81st Padishah Emperor. It's never explained within the original novel who exactly the previous three Shaddams were.
 * The Dune Encyclopedia has a list of every Emperor along with the dates of their reigns. Shaddam IV's immediate predecessors were Fredhrick XIX, Corrin XXV and Elrood IX. Shaddam III reigned 4200 years before Shaddam IV, Shaddam II was some 3000 years before that, and Shaddam I reigned 2400 years before him. Shaddam IV was the 81st "Padishah" Emperor, but the 370th Emperor of the Known Universe.
 * Number 1 was Alexander the Great, so it isn't supposed to be an accurate list.
 * Due to an incident involving a prophylactic and a time-machine, all Zaphod Beeblebroxes are numbered backwards, with the youngest being "Zaphod Beeblebrox I", his father "Zaphod Beeblebrox II", grandfather "Zaphod Beeblebrox III" and so on. A maverick judge in the third novel, who lived millions of years ago, is known as Zipo Bibrok 5x10^8, i.e. Zipo Bibrok (an underlined D), implying that he is a very distant ancestor.
 * Descendant, technically.
 * The Empire-Foundation novels of Isaac Asimov have a few examples in the Galactic Empire's 12,000-year history.
 * Swemmel II, an early monarch named in Pebble in the Sky, Swemmel VII, his not-as-impressive namesake.
 * Millennia later, the final Trantorian emperor Dagobert IX, and his insane son who never gets a chance to become Dagobert X.
 * From what is revealed, the most common name amongst them is Agis (fourteen to be precise). Like the previous examples Agis XIV is nothing like his namesakes, though he didn't really want the job.
 * Cleon II in Foundation in Empire, who took his name in memory of Cleon I, under whom the Empire reached its zenith. In contrast with the aforementioned examples, Cleon II likely surpassed his namesake, as Cleon I was not a forceful monarch and he preferred letting his First Ministers do the real governing, but Cleon II was a very active and powerful emperor.
 * Titus Groan is the 77th Earl of Gormenghast.
 * Ursula K. Le Guin's The Left Hand of Darkness has Argaven XV of Karhide, latest of a dynasty that has lasted 700 years or so. There were a lot of kings before them, though.
 * In the short story Winter's King all the kings of Karhide who aren't called Argaven are called Emran. King Argaven XVII when she finds out that the corrupt Emran,, has chosen an heir with neither of the traditional names.
 * In John Ringo's and David Weber's Empire of Man (aka Prince Roger) space opera series, the 500-year-old dynasty has had ten Emperors and nine Empresses. All but two of the Empresses have been named Alexandra -- Prince Roger's mother is the seventh. His sister is also named Alexandra. One of his middle names is Alexander. No bets as to what his daughter might be named, if he ever has one.
 * Cordwainer Smith's Norstrilia had Roderick Mc Ban CLI.
 * In the Worldwar/Colonization series by Harry Turtledove, the Race is governed by a 50,000 year old imperial dynasty headed by the Ssumaz family. The current emperor is "37th Emperor Risson".
 * Fighting Fantasy gives us King Salamon LVII of the city-state of Salamonis.
 * Averted in Deltora Quest, in which there does not seem to have been more than one monarch with the same name in the country's history. Although the series does end by revealing that Lief and Jasmine named their one of their sons after his father, he is either a second or third son (his brother is named after Jasmine's father, in an aversion of Dead Guy Junior) and likely won't become king.
 * Variation in Codex Alera. The First Lord is Gaius Sextus and the deceased heir was Gaius Septimus, meaning the First Lord is Gaius the 6th and the deceased heir is Gaius the 7th. This becomes a plot point in determining the next heir to the crown
 * Rafik Schami's fictional city of Morgana is technically a democracy with an elected president but practically always ruled by a member of the family Hadahek (a very large and costantly feuding family). At first, the presidents were numbered (President Hadahek LIII) but people soon got fed up with the increasing numbers, and added adjectives intead (President Hadahek the Brave) until they ran out of adjectives. Currently they name their presidents according to their hobbies (President Hadahek the Toy-Collector)
 * Parodied in Verhalen van de tweelingbroers by Tonke Dragt, when one of the main characters suddenly becomes King of Tirania, he has, despite being named Laurenzo, to adopt the name of Sutan the 467th, because all his predecessors have borne that name as well.
 * In the Belgariad novels, the ruler of Tolnedra is always referred to as Ran [House] [Number] of the [Number] [House] Dynasty (If a given Emperor died without male issue, a different noble house would start a new dynasty rather than passing the throne to a brother, nephew or cousin of the previous emperor, with the throne often returning to a house that had held the throne at some other point in history). Arguably subverted when General Varana of House Anadile was adopted as the son of Ran Borune XXIII and took the throne as Ran Borune XXIV instead of Ran Anadile I.
 * The Kings of the Andals, the Rhoynar, and the First Men in A Song of Ice and Fire do this, sometimes more formally as "the Nth of his name." Since the books are set at the beginning of a new dynasty that comes from a different naming culture than the founding dynasty, most of the kings we actually see are only the first of their name, but the previous Targaryen dynasty had racked up five Aegons, two Viseryses, two Jaeheryses, and two Aeryses.
 * Balon Greyjoy is apparently the ninth of his name.
 * While the exact number isn't known, the Starks have had a tradition of naming one son Bran in every generation... going back 8,000 years to Brandon the Builder. Even if only one generation in five had a Bran in charge, and if the average reign was 20 years, that would make the current Bran Stark the 80th of his name.

Live Action TV

 * Mister Rogers Neighborhood had King Friday XIII of the Land of Make-Believe.
 * When Londo Mollari became Emperor of the Centauri Republic (as prophesied by Emperor Turhan's wife early on), he becomes "Emperor Mollari II;" evidently, Centauri nobles chosen Emperor are often known by the names of their Houses (which, fittingly for the Romanesque Centauri, follows Roman practice), and Londo's House Mollari had previously provided one Emperor (when is not revealed).
 * In Farscape, Rygel XVI is a diminutive Dominar-in-exile of the Hynerian Empire, ruler of 600 billion subjects. He was overgrown by his cousin Bishan (whose number is not given) and remained in exile for over 130 cycles. He finally regains his throne in the follow-up graphic novel. His greatest hero is his ancestor Rygel I.
 * Liz-Ten in Doctor Who is actually Queen Elizabeth X of Starship UK.

Tabletop Games

 * Dungeons and Dragons features Vlaakith CLVII, Lich Queen of the Githyanki in the Planescape setting, and through Planescape in pretty much every other setting as well. This Vlaakith, by virtue of being an ancient undead abomination, has also ruled for at least a thousand years, although time doesn't exactly work the same way on their home plane.

Theater

 * Probably implied in Ruddigore. At the time of the play's setting, in the beginning of the 19th century, there are depending on how you look at it, either 22 or 23 "bad baronets" of Ruddigore. As the bulk of baronetcies were from the mid 1600s, it seems a bit short of time for their to have been that many of them. Likely, since they are cursed to die if they don't commit at least one evil act daily, they have a high turn-over rate.

Video Games

 * Chrono Trigger gives us King Guardia XXI, who rules his eponymous nation in the year 600 AD, and his descendent four centuries hence, King Guardia XXXIII.
 * Kingdom of Loathing has King Ralph XI. Who constantly gets imprismed. By a magical, indestructible that somehow keeps coming back.
 * Metroid Prime 3 has this as a borderline Running Gag when you scan busts of Bryyo's ancient rulers found all over the planet... until you reach 'The last emperor of Bryyo'.
 * The plot of the obscure puzzle game Blue Ice begins with the death of Edward the 712th.
 * Princess Garnet is the 17th  person to hold that name. The game doesn't elaborate on how many people have held the name Brahne, but it can be assured that there won't be any more after the game's events.
 * A lesser example from the same game, but the regent of Lindblum is Cid Fabool IX.
 * The Elder Scrolls games have Emperor Uriel Septim VII, the last Emperor of the Septim Dynasty. (Not counting Martin, whose reign lasted the length of Oblivion's main quest.)
 * Note that the Archangel Uriel is traditionally the seventh and last, and Septim being Latin for "seventh".
 * Saga Frontier 2: Gustave XIII, who also had a younger half brother named Gustave.

Web Animation

 * One Strong Bad Email from Homestar Runner had Strong Bad mention that there were actually twelve King of Towns. And for some reason, the fourth King of Town was an onion.
 * He was the most popular one.

Webcomics

 * Erfworld has King Saline the Fourth (IV). Think about it.

Western Animation

 * The minor character King Bushnik the Thirty-Third of Rocky and Bullwinkle seems to invoke this, but then it is revealed that he is the island's first king, who is called that because he lives on 33rd St.
 * The song The Phony King of England from Robin Hood mentioned a suggestion that King John I should be now known as King John "the Worst!"

Real Life

 * Regnal numbering only began in 12th or 13th century Europe; numbers prior to this have been applied in retrospect by historians. Before this, monarchs were distinguished by nicknames, e.g. the English kings Edmund the Magnificent and Edmund Ironside) or by paternity.
 * This is why Edward Longshanks of The House of Plantagenet (r. 1272-1307) is called Edward I even though three previous Edwards (Edward the Elder, Edward the Martyr, and Edward the Confessor) had been King of England (well King of the English...) before the Norman Conquest of 1066.
 * James I and James II are properly "James I and VI" and "James II and VII" (of England and Scotland respectively), double dipping this trope. Most of the other monarchs of the UK, both before and after the act of Union, haven't recycled names from before the Scottish and English thrones merged. Current protocol is that the higher number takes precedence, hence William IV, Edward VII, Edward VIII and Elizabeth II. Mary II is a slightly odd case since the number for England and Scotland matches up.
 * The British monarchy is also relatively tame on this trope and none of the numbers have gotten into the double digits yet. Eight Henries and Edwards, seven Jameses and six Georges.
 * Averted with King Stephen, King John and Queen Anne. No numbers since they're the only monarchs to bear that name on the English/British throne. Anne doesn't stand out since there haven't been that many reigning queens but Stephen hasn't been recycled since 1154 and John since 1216. (Not all that surprising, since King Stephen reigned during a disastrous civil war and King John is pretty much a byword for awful - these are pretty much seen as unlucky names, and avoided when naming royal offspring. Queen Anne, on the other hand, was quite a successful monarch, so the current queen had no problem using that name for her daughter.)
 * In the (somewhat unlikely) event that Prince Harry became king, he would likely be Henry IX.
 * Pope John XXIII (actually the 21st Pope of this name, due to some confusion in numbering). Also Benedict XVI, Gregory XVI, Pius XII, Leo XIII, Clement XIV, Innocent XIII. The last Pope to have an original name was Lando (no, honestly!), reigned AD 913-914 (unless one counts "John Paul" as original).
 * Margaret of Mar (born 1940), 31st Countess of Mar and 24th Lady Garioch
 * In fact, the French had approximately 18 kings named "Louis". And one Louis-Phillippe. Oh, and ten named Charles. The current heir to the house of Bourbon styles himself as Louis XX (Louis XIX having been the nominal last king of France for 20 minutes in 1830).
 * Deliberately invoked from the 17th Century through to the French Revolution: every heir in direct line for the throne was given the first name Louis, for eight generations beginning with Louis XIII. In fact, Louis XVI and Louis XVIII were brothers, both named Louis but with different middle names.
 * Carl XVI Gustav of Sweden (although he is probably only the 10th king named Carl/Charles/Carolus - it's complicated
 * Heinrich LXXII, Prince of Reuss-Lobenstein-Ebersdorf. But unlike with most European monarchies, his number does not indicate that he was preceded by 71 previous rulers also named Heinrich. By tradition, all male members of the House of Reuss are named Heinrich, and are numbered by order of birth within the family in general. In the Reuss Younger Line, the numbering system was reset at the beginning of each century; thus Heinrich LXXII's high number is directly related to his having been born at the very end of the 18th century (1797).
 * This is an Enforced and Exaggerated example of Naming After Somebody Famous; the House of Reuss requires all male descendents to be named Heinrich after Henry (Heinrich) VI, Holy Roman Emperor.
 * Ancient Egypt was ruled by thirty-three separate dynasties over the course of 3,000 years.
 * Surprisingly, only two names (Rameses and Ptolemy) were used more than 8 times (11 and 15, respectively). See, time is no excuse for lack of originality!
 * The Cleopatra who wooed Caesar and Marc Antony was actually Cleopatra VII.
 * Another real life example; the kings of Thailand, who have traditionally adopted the regnal name "Rama" since the late 18th century. The current monarch, Bhumibol Adulyadej, has the regnal name Rama IX.
 * In the British peerage, a hereditary peer of the realm will be styled "The Nth Duke of Earl." If a title lapses and is later created again, the numbering starts over again. E.g., Andrew Russell is the 15th Duke of Bedford, of the Fifth Creation (1694) of that title; the First Creation was in 1414; and before that, there were two creations of Earls of Bedford. It gets confusing.
 * In the Eastern Ijaw Kingdoms of Nigeria (Okrika, Opobo, Bonny, Kalabari, Nembe), kingship is the property of a particular War Canoe House (a trading company), and with its Chief becoming the Monarch. Each monarch officially reigns under the House name, adopting the regnal number following his predecessor. Most of them are in the double digits now.
 * Subverted with the actor David H. Lawrence XVII. He is not the seventeenth David H. Lawrence in his family... he is the seventeenth David H. Lawrence to be registered on IMDB.