"Erika" (German: [ˈeːʁɪka] ^ⓘ), also known by its incipit "Auf der Heide" (On the Heath), is a German marching song with words and music by Herms Niel and published in 1938 during the Nazi regime.^[1][2] The song was then soon used as a soldier song by the Wehrmacht. According to British soldier, historian, and author Major General Michael Tillotson, it was the most popular marching song of any country during the Second World War.^[3]

The exact year of the song's origin is not known; often the date is given as "about 1930",^[4] but this has never been substantiated. The song was originally published in 1938 by the publishing firm Carl Louis Oertel [de] in Großburgwedel, a village northeast of Hanover, Lower Saxony, but it had been popular prior to that.^[5]

"Erika" is both a common German female name and the German word for heather. After each line, and after each time the name "Erika" is sung, there is a three-beat pause, which is filled by the timpani or stamping feet (e.g. of marching soldiers), shown as (xxx) in the text below.

• In June 2024, members of the University of Warwick Conservative Association sang and danced to this song during an annual event.^[7][8] University of Warwick representatives condemned the actions of the students.^[9] The association stressed that it was requested by a single member who was "no longer welcome", and apologised for any offence caused.^[10]