Between April 27, 1949 and May 23, 1949, four bills of identical language were introduced in the House of Representatives calling for the "coinage of 50-cent pieces to commemorate a century of railroad operations out of Chicago, IL, and to commemorate the Chicago Railroad Fair of 1948-49."
The Chicago Railroad Fair was conceived by the Chicago and North Western Railway (CNWR). The CNWR was the successor to the first rail company that operated out of Chicago - the Galena & Chicago Union Railroad. At the time, the CNWR still owned the
Pioneer, the locomotive that pulled the first Galena & Chicago Union train out of Chicago in October 1848.
1948 Chicago Railroad Fair - Official Guide Book / Program
The Fair opened on July 20, 1948 and ran through Labor Day (September 6, 1948). It opened again on June 25, 1949 and ran through October 2, 1949. Railroad companies from across the country participated - 39 in total. Over its two-season run, the Fair drew approximately 5.5 million attendees to its grounds on the shores of Lake Michigan; admission cost $1.00 though it's likely that many attendees received free admission passes.
The bills were introduced by Gerald Rudolph Ford. Jr. (R-MI) - the future Vice President and President of the US, Thomas Joseph O'Brien (D-IL), Paul Werntz Shafer (R-MI) and Barratt O'Hara (D-IL). Each of the bills was referred to the House Committee on Banking and Currency. The coins were to be struck for the benefit of the Chicago Railroad Fair, but the City National Bank and Trust Company of Chicago was to have the financial responsibility for the coins.
The bills included a few provisions that challenged their approval:
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500,000 coins were requested - a very large number for a bill introduced in 1949 (though fewer than the recently enacted Booker T. Washington Birthplace Memorial bill which was approved for 5,000,000 coins);
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a "back dating" provision was included for a portion of the coins to be struck, 50,000 coins were to be dated "1948" even though the Mint would be striking the coins in 1949; the remaining 450,000 coins were to be dated "1949";
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no limits to where the coins could be struck - coins could be ordered struck at any US Mint facility (i.e., a three-coin P/D/S set was entirely possible for each year's issue); and
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no order size restrictions were put in place, thus opening the door for small releases (e.g., 2,000 1949-S coins).
On the positive side of the ledger, the coins could only be issued during calendar year 1949.
None of the four bills were reported out of Committee and so were never considered on the House or Senate floor; they all died for lack of action when the 81st Congress adjourned.
I'm aware of a privately-struck souvenir medal for the 1949 Chicago Railroad Fair. The brass examples I've seen are all low-relief pieces and not on par with the design or engraving quality of a US Mint coin or medal, but at least the Fair did have some type of numismatic souvenir.
For more of my topics on commemorative coins and medals, including more What If? stories, see:
Commems Collection.