Near the
hamlet of Ruderbaum, the remains of a
Horgen culture settlement have been discovered. Below the Horgen site, there also may be a
Pfyn culture site, but that is less certain. The modern village of Altnau may be first mentioned in 787 as
Althinouva. In the 8th Century the
Abbey of St. Gall owned most of the land in Altnau. In 1155, Emperor
Friedrich Barbarossa confirmed that the Cathedral of
Constance owned the church and church yard in the village. The
vogt right over the church's farms belonged to the
Freiherr of Altenklingen after 1300. During the
Late Middle Ages, this right was given to several noble families from Constance; 1378 Schwarz, 1430 Tettikofen, 1468 Mangolte, and from 1471 until 1798 the city of Constance directly controlled the farms. In 1454 the villagers were represented in the
Appenzell Landrecht, but following complaints from Constance they were forced to give up their membership. The rights of the village are first listed in the
Gerichtsoffnung of 1468. (1924) The right to administer the
parish of Altnau went from the cathedral's
provost to the cathedral's
dean in 1347. After the
Protestant Reformation in 1528, the few remaining Catholics were looked after by Constance and the village church became a
shared church. This situation remained until 1810 when two churches were completed. Until the 19th Century, most of the local economy revolved around
three-field agriculture. About 1880 a dairy company was founded in the village, and livestock and cheese production became common.
Viticulture was common from the
Middle Ages until 1912. In 1840 the
Seestrasse (Lake Road) was built, and in 1870, the
Seetalbahn (railroad line) was added. However, neither the road or the railroad led to a boost in the local economy, as the station was too far away. ==Geography==