Werdenberg was a county of the Holy Roman Empire situated on either side of the Rhine, including parts of what is now St. Gallen (Switzerland), Liechtenstein, and Vorarlberg (Austria). It is named for Werdenberg Castle, today located in the municipality of Grabs in the Swiss canton of St. Gallen. It was partitioned from Montfort in 1230. In 1260, it was divided into Werdenberg and Sargans, in 1308 Werdenberg was further divided into Werdenberg-Heiligenberg and Werdenberg-Werdenberg. The Vaduz line of Counts of Werdenberg died out in 1406 and Vaduz passed to the Barons of Brandis.