King Frederick I's Württemberg was given high status in the Confederation of the Rhine among the College of Kings, and the lands of nearby secondary German states. Within Stuttgart, the royal residence was expanded under Frederick although many of Stuttgart's most important buildings, including Wilhelm Palace, Katharina Hospital, the State Gallery, the Villa Berg and the Königsbau were built under the reign of King Wilhelm I. In 1818. King Wilhelm I and Queen Catherine in an attempt to assuage the suffering caused by the Year Without Summer and following famine, introduced the first Cannstatter Volksfest to celebrate the year's bountiful harvest. Hohenheim University was founded in 1818, and two years later the Württemberg Mausoleum as completed on the hill where Wirtemberg Castle once stood.