|• Mayor||Gerhard Martin (SPD)|
|• Total||77.13 km2 (29.78 sq mi)|
|Elevation||402 m (1,319 ft)|
|• Density||120/km2 (300/sq mi)|
|Time zone||CET/CEST (UTC+1/+2)|
The earliest reference to Rain is in a document of the Niederschönenfeld monastery dated 4 July 1257, wherein it is described as a "civitas nostra" or ducal town. It is most probable that Rain was founded during the reign of Otto II Wittelsbach, Duke of Bavaria (1248–1253) or at the latest in the reign of Louis II, Duke of Bavaria (1253–1294) before 1257.
On 15 April 1632 during the Thirty Years War the Battle of Rain took place. The Protestant army of Gustavus Adolphus of Sweden defeated the army of the Catholic League commanded by Johann Tserclaes von Tilly. Tilly withdrew his troops to Ingolstadt, where he died from tetanus from an infected gunshot wound in his thigh.
In 1914 a monument commemorating Tilly was erected in front of Rain's Rococo town hall. Rain's architectural heritage also includes the Roman Catholic parish church of St John the Baptist, which features late Gothic frescoes dating from about 1480. There is also the Schwabian Gate, the historic Spital with its All Saints' chapel and the former Castle.
Rain has three museums: the Lachner Brothers Museum, Homeland Museum and Jean-Duprai-Museum. The four Lachner brothers, Theodor, Franz, Ignaz and Vinzenz, were nineteenth-century German composers, all of whom were born in the town.
- Otto Spreitler, temporary (1945)
- Josef Müller (1945–1948)
- Carl Faig (1948–1966)
- Karl Würmseher, PWG (1966–1990)
- Gerhard Martin, SPD (since 1990)
- Georg Tannstetter, called Collimitius (1482-1535), Scholar and Humanist
- Johannes Bayer (1572-1625), jurist and creator of the Uranometria
- Franz Lachner (1803-1890), musician
- Ignaz Lachner (1807-1895), musician
- Vinzenz Lachner (1811-1893), musician
- Michael Raucheisen (1889-1984), pianist and composer
- Georg Weber (1910-1986), entrepreneur
- Dieter Reiter (born 1958), politician (SPD), Mayor of Munich since May 2014
- "Fortschreibung des Bevölkerungsstandes". Bayerisches Landesamt für Statistik und Datenverarbeitung (in German). September 2018.