Rüti Abbey
Elsau is first mentioned in 1043 as "Elnesouva". On 23 April 1398 Count "Donat von Toggenburg, Herr zu Brettengow und Tavas" donated the church of "Elsow" as benefice for the new "Allerheiligenaltar" at the grave of the Toggenburg family in the Rüti Abbey, for the "salvation of his daughter soul Menta von Toggenburg" who died shortly before, as well as further lands and goods in the present "Weinland" district of the canton of Zürich, confirmed among others by "Ruodolf von Bonstetten" from "Ustra.