Chester Beach (b. 1881; d. 1956) has one of the more
interesting biographies among those who are credited with designing a classic-era United States ("US") commemorative coin.
He is connected to four coins of the era, but I'm hard-pressed to give him full design credit for any of those with which he was involved.
The four commemorative half dollars are: 1923
Monroe Doctrine Enunciation Centennial, 1925 Battle of Lexington-Concord Sesquicentennial, 1928 Hawaiian (European) Discovery Sesquicentennial and 1935 Hudson, New York Sesquicentennial. In each case, he modeled the artistic creations of another artist for the coin.
The reverse design of the 1923
Monroe Doctrine Enunciation Centennial Half Dollar was noticeably
influenced by an earlier design created by Ralph Beck for the 1901 Pan-American Exposition held in Buffalo, NY.
Button with Logo of 1901 Pan-American Exposition
1923 Monroe Doctrine Enunciation Centennial Half Dollar

Check out:
1923 Monroe Doctrine Centennial - Ancestors for more details.
The 1925 Battle of Lexington-Concord Sesquicentennial Half Dollar is another Beach design that is rooted in a previous artist's work - in this instance,
The Minute Man statue in Lexington that is seen on the coin's obverse. The statue was sculpted by Daniel Chester French between 1871 and 1874; it was officially unveiled in 1875 as part of the festivities for the centennial of the battle.
1925 Battle of Lexington-Concord Sesquicentennial Half Dollar

For more, see:
1925 Battle Of Lexington-Concord Sesquicentennial, The Minute ManThe 1928 Hawaiian (European) Discovery Sesquicentennial Half Dollar was a case of Beach modeling the design sketches of another artist - Juliette May Fraser.
1928 Hawaiian (European) Discovery Sesquicentennial Half Dollar

See:
Post Your Coins And Medals Designed By A WomanLastly, the 1935 Hudson, New York Sesquicentennial Half Dollar features a design closley modeled after the existing City Seal.
1935 Hudson, New York Sesquicentennial Half Dollar

I discussed the connection here:
Official Seals On Classic US Commemoratives - Part IIINothing I've written here is meant to disparage the reputation of Chester Beach. He is a noted artist/sculptor who has created a wealth of outstanding works - his skills are undeniable. But in the world of US commemorative coins, I think it's fair to say that he had good source material from which to start.
Here's one of his more famous/popular medallic works:
1937 Society of Medalists - 1937 Fathers/Sons Medal - Chester Beach
(Image Courtesy National Gallery of Art, Washington.)For other of my posts about commemorative coins and medals, including more about each of the coins discussed here, see:
Commems Collection