Also, I recently learned, a possible Soviet agent: I. F. Stone - Wikipedia
IG - Inspector General
Typically an investigative official in a civil or military organization. In Vatican City, however, the Inspector General is the commanding officer of the state police force, the Corps of Gendarmerie of Vatican City. He is also the chief bodyguard for the Pope, accompanying him when visiting foreign countries.
IH = International Harvester, manufacturer of agricultural machinery and construction equipment.
II = Indianapolis, Indiana
When paired with Annapolis, Maryland, is the wrong answer to the question what two state capitals end with the longest string of the same letters. They both end with the 7-letter string -napolis, but the correct answer is Carson City and Jefferson City, which both end with -rsoncity, a string of eight letters.
II - Indianapolis, Indiana. Best known for the Indianapolis 500 motor race, which is not actually held in Indianapolis, but in the separate town of Speedway, an enclave in the city of Indianapolis.
ETA: Ninjaed by jtur88, but we did have different facts!
I’ll make up for that by giving another city that I have visited.
IJ - Izumo, Japan. This city is best known for the Izumo-taisha, probably the oldest Shinto shrine (the date of its founding is unknown).
IK- Philosopher Immanuel Kant (a real pissant who was very rarely stable) came up with the moral concept of the Categorical Imperative in his “Critique of Pure Reason.”
IL = Iowa, Louisiana, population around 3,000. Iowa experienced a growth boom when oil was struck in 1930 and oil companies came to try their luck in the Iowa oil and gas fields. Even though this was the Great Depression era, Iowa thrived as more men came to work in the oil fields. Today, oil continues to be a vital part of the town’s economy, as are farming and cattle. The town of “Iowa” is actually pronounced with the long A sound at the end (i-o-way), as opposed to the pronunciation of the state of Iowa.
IM = Infinite Monkeys
The Infinite Monkey Theorem argues that an infinite number of monkeys with typewriters will eventually type the complete works of Shakespeare. Bob Newhart did a bit on a monitor in the room, checking what the monkeys type: "Hey, look, Fred, we might have something here – “To be or not to be, that is the bkrfhtymy”
IN = Iqaluit, Nunavut.
A city of 7,000, formerly known as Frobisher Bay, Northwest Territories, Canada. Iqaluit is the only place where Google Streetview camera is mounted on a sled pulled by a dog team
IO - For one season, 1978-79, English actor Ian Ogilvy starred on "Return of the Saint, an ITV series in which he played Leslie Charteris’ most famous creation, Simon Templar. The series was unsuccessful, but led to brief speculation that Ogilvy might replace Roger Moore as the movie James Bond.
Moore himself had played Simon Templar in the 1960s series “The Saint.”
IP - Intellectual property
According to Wiki, the phrase “refers to creations of the intellect for which a monopoly is assigned to designated owners by law… and include trademarks, copyright, patents, industrial design rights, and in some jurisdictions trade secrets. Artistic works including music and literature, as well as discoveries, inventions, words, phrases, symbols, and designs can all be protected… [It] was not until the 19th century that the term intellectual property began to be used, and not until the late 20th century that it became commonplace in the majority of the world.”
IQ = Intellectual Quotient. Estimated IQs for various presidents (see here) are: George Washington - 130, John Adams - 145, Thomas Jefferson - 150, John Quincy Adams - 165, Ulysses S. Grant - 120, Woodrow Wilson - 145, FDR - 130, JFK - 150, and Barack Obama - 145.
IR =Indian Railways
Indian Railways has over 55,000 passenger cars, and carries 22-million passengers a day.
IS- Guitarist Izzy Stradlin and singer Axl Rose of Guns & Roses grew up together in Lafayette, INdiana, where their names were Jeff Isbell and Bill Bailey.
IT = Ike Turner, early rock & roll performer and husband to Tina. Turner said that when he was very young he witnessed his father beaten and left for dead by a white mob. His father lived for three years as an invalid in a tent in the family’s yard before succumbing to his injuries. Writer and blues historian Ted Drozdowski told a different version of the story, stating that Turner’s father died in an industrial accident.
IU - Islamabad United
Per Wiki, “Islamabad United (Urdu: اسلامآباد یونائیٹڈ) is a Pakistani professional franchise cricket team that competes in the Pakistan Super League (PSL). The team is nominally based in Islamabad, the capital city of Pakistan, and was formed in 2015 to compete in the first season of the Pakistan Super League. The franchise won the first PSL title, defeating Quetta Gladiators in the final.”
IV = Intransitive Verb
A verb that has no direct object.
IW = Irish Wolfhound. The breed is very old; there are suggestions it may have been brought to Ireland as early as 7000 B.C. These dogs are mentioned, as cú (variously translated as hound, Irish hound, war dog, wolf dog, etc.) in Irish laws and in Irish literature which dates from the 5th century or, in the case of the Sagas, from the old Irish period - AD 600-900. The word “Cu” often became an added respected prefix on the names of warriors as well as kings denoting that they were worthy of the respect and loyalty of a Cu.
IX = International XT
A range of pickup trucks produced by Navistar International from 2004 to 2008.
IY = InuYasha, a Manga and Anime series of some great length. It has been shown in the USA on Adult Swim.