Question: Who was the creator of a fictional town setting for the program Prairie Home Companion created in 1974?

Context articles: A Prairie Home Companion
Vern Sutton
Prairie Home Invasion
Tom Keith
A Prairie Home Album
Garrison Keillor
Fitzgerald Theater
A Prairie Home Companion with Chris Thile
Lake Wobegon
American Public Media

A Prairie Home Companion is a live weekly radio variety show hosted by musician and songwriter Chris Thile.
 The program was created in 1974 by Garrison Keillor, who hosted it until 2016.
 It airs on Saturdays from 5 to 7 p.m. Central Time, from the Fitzgerald Theater in Saint Paul, Minnesota; it is also frequently heard on tours to New York City and other US cities.
 The show is known for its musical guests, especially folk and traditional musicians, tongue-in-cheek radio drama, and relaxed humor.
 Keillor's wry storytelling segment, "News from Lake Wobegon", was the show's best-known feature during his long tenure.
Vern Sutton (born April 8, 1938) is an American operatic tenor, opera director, and academic.
 A founding member of the Minnesota Opera, he has created roles in the world premieres of several contemporary operas with that company; including works composed for his voice by Dominick Argento, Libby Larsen, Eric Stokes, Conrad Susa, and Robert Ward.
 He was also a regularly featured singer on Garrison Keillor's "A Prairie Home Companion" for three decades, beginning with its first broadcast in 1974.
Prairie Home Invasion is an album released by Jello Biafra with Mojo Nixon in 1994.
 The title is a play on the popular public radio program "A Prairie Home Companion" and the Ice-T album "Home Invasion".
 There was also a single released for "Will The Fetus Be Aborted?"
 which included an outtake from this album titled "The Lost World" and a parody of Billy Ray Cyrus's "Achy Breaky Heart" titled "Achy Rakey Heart" as B-Sides.
Thomas Alan Keith (December 21, 1946 – October 30, 2011) was a radio personality who worked for Minnesota Public Radio in St. Paul, Minnesota.
 He was the engineer for Garrison Keillor when the latter began his early morning radio show from the St. John's University, Collegeville, Minnesota studio.
 Keillor wanted dialogue during the program and Keith was about the only other person around at that early hour.
 Keith was one of the primary sound effects performers for the radio show "A Prairie Home Companion" and was often an actor in sketches written by Keillor.
 Keillor created the persona of Jim Ed Poole for Keith on the old early morning show.
 Jim Ed was said to have grown up in West St. Paul, Minnesota and graduated from Henry Sibley High School.
A Prairie Home Album is an album from the Prairie Home Companion radio show.
 It features items written for the early days of the program, when it was a morning show broadcast from KSJN in St. Paul, MN.
Gary Edward "Garrison" Keillor (born August 7, 1942) is an American author, storyteller, humorist, voice actor, and radio personality.
 He is best known as the creator of the Minnesota Public Radio show "A Prairie Home Companion" (called "Garrison Keillor's Radio Show" in some international syndication), which he hosted from 1974 to 2016.
 Keillor created the fictional Minnesota town Lake Wobegon, the setting of many of his books, including "Lake Wobegon Days "and "".
 Other creations include Guy Noir, a detective voiced by Keillor who appeared in "A Prairie Home Companion" comic skits.
The Fitzgerald Theater is the oldest active theatre in Saint Paul, Minnesota, and the home of American Public Media's "A Prairie Home Companion".
 It was one of many theaters built by the Shubert Theatre Corporation, and was initially named the Sam S. Shubert Theater.
 It was designed by the noted Chicago architectural firm of Marshall and Fox, architects of several theaters for the Shuberts.
 In 1933, it became a movie outlet known as the World Theater.
 The space was purchased by Minnesota Public Radio in 1980, restored with a stage in 1986 as a site for "Prairie Home", and renamed in 1994 after St. Paul native F. Scott Fitzgerald.
The live weekly radio variety show, A Prairie Home Companion with Chris Thile, whose title indicates the new program host, musician Chris Thile, derives from the historic "A Prairie Home Companion with Garrison Keillor" ("APHC") radio show, where the changeover in the onstage hosting and program began on October 15, 2016.
 Thile, an American virtuoso mandolinist and singer-songwriter, had a two decade history with "APHC" and is known for his work in the folk and progressive bluegrass groups Nickel Creek and Punch Brothers.
 After two unprecedented guest host spots in 2015, Keillor decided on his successor, featured Thile as host again in January–February 2016, and fully ceded his hosting role to Thile in the October 2016 performance at the Fitzgerald Theater in St. Paul, Minnesota, continuing as the show's Executive Producer.
 As of 1 November 2016, the new program presents expanded musical and comedic elements, retaining the template of the earlier program (e.g., its most recent acting and sound effect cast, and "sponsorships" from faux companies), but without such features as its earlier signature "Lives of the Cowboys" series and "News from Lake Wobegon" monologue.
 Early reviews of the new program have been uniformly positive, focusing on the remaining familiar elements and on the new music and expanded musical focus brought by the new host.
Lake Wobegon is a fictional town created by Garrison Keillor to provide the setting for the long-running radio broadcast, "Prairie Home Companion".
 Lake Wobegon is also the setting for many of Keillor's stories and novels.
 It is described as a small rural town in central Minnesota, and it is peopled with fictional characters and places, many that have become familiar to listeners of the broadcast.
 The events and adventures of the imaginary townspeople provide the prolific Keillor with a wealth of stories, that are humorous and at times touching and thoughtful.
Based in St. Paul, Minnesota, APM is best known for the distribution of the popular weekend program "A Prairie Home Companion" and the national financial news program "Marketplace".