The town is situated between the south-west and north-east part of the Wiener Becken, on a sea level of 202 m. Trumau spreads over 18,57 km² and houses 3465 inhabitants.

The town was founded during the late Middle Ages, as a gift from the Babenberger Leopold IV to the Heiligenkreuz monastery.

In ancient documents, Trumau appears in the following versions: between 1137-1340: Trumowe, 1139 Drumau, 1178 Drumawe, between 1233 and 1294 Drumowe, between 1303 and 1306 Drumbuowe, 1340 Drumenaw, 1380 Drumpnaw, 1388 Drumpnow, 1463 Thrumbaw.

In the course of the counter-reformation, Emperor Rudolph II and Bishop Urban got the approval of Abbot Udalricus Molitor [de] to build the parish church of Trumau in 1583.

The church was finished under Abbot Johannes Rueff [de], and it was consecrated by Bishop Hector Wegmann of Passau on 22 February 1588.