Sheil, MissouriSheil is an unincorporated community in Ralls [County, Missouri|Ralls County], in the U.S. state of Missouri.HistoryVariant names were "Shiel" and "Sydney". A post office operated under the name "Sydney" as early as 1855. The name was changed to "" in 1898, and the post office was discontinued in 1910. Shiel was named after a local priest.