Classic-era US commemorative coins were issued for a variety of reasons, with many tied to significant anniversary milestones such as: statehood anniversaries, municipal anniversaries, battle anniversaries, colonial history anniversaries, etc. There is also a reasonably large subset of coins from the early series that is directly tied to an Exposition.
I recognize that many of the series' coins are connected to events whose observance included public events such as parades or pageants, but those celebrations don't rise to the level of a weeks- or months-long fair or exposition that included exhibition halls with displays from multiple countries and states. By my count, there are at least 15 coins that were formally linked to a full-fledged fair/exposition via language in their authorizing Acts:
No. Year Coin Fair / Exposition
1. 1892-93 Columbus Half Dollar World's Columbian Exposition (Chicago, IL)
2. 1893 Isabella Quarter Dollar World's Columbian Exposition (Chicago, IL)
3. 1900 Lafayette Dollar Exposition Universelle of 1900 / 1900 Paris Exposition (Paris, France)
4. 1903 Louisiana Purchase Gold Dollar
(Jefferson) Louisiana Purchase Exposition (St. Louis, MO)
5. 1903 Louisiana Purchase Gold Dollar
(McKinley) Louisiana Purchase Exposition (St. Louis, MO)
6. 1904-05 Lewis and Clark Gold Dollar Lewis and Clark Centennial and American Pacific Exposition and Oriental Fair (Portland, OR)
7. 1915 Panama-Pacific Half Dollar Panama-Pacific International Exposition (San Francisco, CA)
8. 1915 Panama-Pacific Gold Dollar Panama-Pacific International Exposition (San Francisco, CA)
9. 1915 Panama-Pacific Gold Quarter Eagle Panama-Pacific International Exposition (San Francisco, CA)
10. 1915 Panama-Pacific Gold Quintuple
Eagle - Round Panama-Pacific International Exposition (San Francisco, CA)
11. 1915 Panama-Pacific Gold Quintuple
Eagle - Octagonal Panama-Pacific International Exposition (San Francisco, CA)
12. 1926 Sesquicentennial Half Dollar Sesqui-Centennial International Exposition (Philadelphia, PA)
13. 1926 Sesquicentennial Gold Dollar Sesqui-Centennial International Exposition (Philadelphia, PA)
14. 1935-36 San Diego Half Dollar California-Pacific International Exposition (San Diego, CA)
15. 1936 Cleveland. OH Centennial Great Lakes Exposition (Cleveland, OH)Honorable Mentions- 1921 Missouri Centennial Half Dollar: Missouri Centennial Exposition and State Fair (Sedalia, MO)The coin features the name of the city in which the Centennial Exposition was held ("Sedalia") and coins were available for purchase at the Exposition.
- 1923 Monroe Doctrine Half Dollar: American Historical Revue and Motion Picture Historical Exposition (Los Angeles, CA)Officially, the coin was issued to mark the 100th anniversary of the enunciation of what came to be known as the Monroe Doctrine. Its Act did not specifically mention the American Historical Revue and Motion Picture Historical Exposition by name, but it was associated "once-removed" via the listed sponsor's (the Los Angeles Clearinghouse) association with the Exposition group.
- 1925 California Statehood Half Dollar: (San Francisco, CA)The State held a week-long celebration that featured participation from across the state, and included multiple parades, automobile races, several bands, numerous athletic events and diverse nightly entertainment. It did not include exhibit halls with displays by foreign nations, but it did include British sailors and marines plus Japanese sailors who all took part in the military parade on Army and Navy Day.
- 1934-38 Texas Centennial Half Dollar: Texas Centennial Exposition (Dallas, TX)Many collectors link the Texas Centennial half dollars to the State's Centennial Exposition, but the two were sponsored/managed by different groups and proceeds from the coins were earmarked for a State Museum, not financial support of the Exposition.
My posts on all of the coins listed above, plus other commemorative coins and medals, can be found by checking out:
Commems Collection.