Through grants by the Holy Roman Emperor, the prince-bishops of Speyer established themselves as worldly as well as spiritual rulers.

The Diocese of Speyer in its current form was established within the borders of the former Rheinkreis, a district of the Kingdom of Bavaria in 1817 after the secularization and division of the former bishopric in 1803.

[2] In 1985, Pope John Paul II elevated former Speyer bishop Friedrich Wetter to be a cardinal.

In April 2020, a Nigerian priest in the Diocese of Speyer quit after “massive” racist threats and abuses were showered upon him.

[4][5] In early 2020, a German court took testimony that during the 1970s, nuns in the Diocese of Speyer had aided and abetted sexual abuse of children at a children’s home, after a legal complaint was filed; the Diocese settled the case in December of that year for €15,000.