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.
Geography
Elsau has an area of. Of this area, 56.5% is used for agricultural purposes, while 25.7% is forested. Of the rest of the land, 17.2% is settled and the remainder is non-productive. housing and buildings made up 10.9% of the total area, while transportation infrastructure made up the rest. Of the total unproductive area, water made up 0.5% of the area. 15.4% of the total municipal area was undergoing some type of construction. The municipality is located along both banks of the Eulach river. It consists of the villages of Elsau, Rümikon, Räterschen and since 1922 the villages of Unter- and Oberschottikon.
Demographics
Elsau has a population of. , 11.9% of the population was made up of foreign nationals. the gender distribution of the population was 50.1% male and 49.9% female. Over the last 10 years the population has grown at a rate of 14.5%. Most of the population speaks German , with Italian being second most common and Albanian being third. In the 2007 election the most popular party was the SVP which received 39.5% of the vote. The next three most popular parties were the SPS, the FDP and the CSP. The age distribution of the population is children and teenagers make up 25.4% of the population, while adults make up 61.4% and seniors make up 13.2%. The entire Swiss population is generally well educated. In Elsau about 80.2% of the population have completed either non-mandatory upper secondary education or additional higher education. There are 1143 households in Elsau. Elsau has an unemployment rate of 2.33%. , there were 67 people employed in the primary economic sector and about 26 businesses involved in this sector. 237 people are employed in the secondary sector and there are 42 businesses in this sector. 464 people are employed in the tertiary sector, with 102 businesses in this sector. 55.2% of the working population were employed full-time, and 44.8% were employed part-time. there were 817 Catholics and 1633 Protestants in Elsau. In the 2000 census, religion was broken down into several smaller categories. From the, 59.7% were some type of Protestant, with 56.1% belonging to the Swiss Reformed Church and 3.6% belonging to other Protestant churches. 23.7% of the population were Catholic. Of the rest of the population, 0% were Muslim, 4.3% belonged to another religion, 2.4% did not give a religion, and 9.6% were atheist or agnostic. The historical population is given in the following table:
