 The town remained in Habsburg possession throughout the 14th century, administrated by the counts of Toggenburg from 1314, 
and by Heinrich Gessler of Meienberg from 1374.Gessler improved the castle fortifications against the threat of the Swiss Confederacy in the years leading up to the Sempach War, and Grüningen was raided several times by Zürich during the 1370s to 1380s.Heinrich Gessler died in 1403 and was succeeded by his son Hermann, who was finally forced to cede Grüningen to Zürich.