[4] A manuscript from 1239 references a Romanesque chapel in the center of Heidelberg named “Zum Heilien Geist” (English: to the Holy Ghost).

Sermons had been delivered in German at various points before the Reformation at the Church of the Holy Spirit, but Protestantism was not quickly adopted in Heidelberg.

Otto Henry's successor, Friedrich III, converted the church to Calvinism and commissioned the Heidelberg Catechism.

[3] In 1706, a succession crisis resulted in the church being divided in half in order to accommodate both Catholics and Protestants simultaneously, so that both congregations could hold their services without any mutual disturbance.

[3] During the Thirty Years War, this collection of manuscripts and early printed books were taken as loot and presented to the Pope by the Count of Tilly, who commanded the Catholic League’s forces at Heidelberg in 1622.

[citation needed] During the Palatinate War of Succession, the church was raided by French forces in 1693 and significantly damaged by a fire.

A viewing platform inside the main spire is accessible to the public via a narrow staircase with a total of 208 steps.

To replace the damaged windows, emergency glazing was introduced in the 19th century, principally in the choir and along the south aisle of the nave.

In the mid-1970s, the regional church board voted to replace the 19th century additions, as part of a broader restoration and repair of the interior.

[5] As a result, two significant efforts were made in the 1970s and 1990s to reinstall stained glass into these windows through a programme of artworks by a single artist.

[8] Initially, the German artist Johannes Schreiter was commissioned in 1977 to undertake the project and design a total of twenty-two pieces, but negative response to his designs and the resulting Heidelbergerfensterstreit (‘Heidelberg Window Controversy’) meant that only one complete work, the Physikfenster (‘Physics Window’) was made and installed into the church, in 1984.

His resulting designs drew on the history of the site's location as the repository of the Biblioteca Palatina and its link to the development of Calvinism through the 1563 Heidelberg Catechism.

[citation needed] During the late 1990s, Hella Santarossa won a subsequent 1997 competition for a series of five windows whose core element is treated, broken coloured glass.

The resulting avant-garde designs, which incorporated references from science, medicine, philosophy, and the analogue technologies of the day, became the subject of a cultural and theological dispute known as the "Heidelberg Controversy" (German: Heidelbergerfensterstreit Fensterstreit).

[13] Schreiter's designs had previously been debated and tested within a focus group including theologians, art critics, and church attendees.

[14] Schreiter had originally been commissioned to create ten separate pieces for the nave; the ensuing controversy caused the remaining nine to be abandoned.

Only two points on the piece are in bright blue: one highlighting Albert Einstein's mass–energy equivalence, E=mc2, and the other states the date the first atomic bomb was dropped on Hiroshima, 6 August 1945.

This theme is reflected in Schreiter's work by an effect in the glass that resembles burnt paper near the date of the Hiroshima tragedy.