According to the latest research, it has been proven that Diedorf was already mentioned in a document in 817 and was therefore able to look back on a 1200-year anniversary in 2017. This makes Diedorf the oldest and second-largest village in the rural municipality of Südeichsfeld.

The village lies in a valley surrounded by the foothills of the Hainich. From the summit of the Dörnerberg, which lies to the south-east and is almost 480 m high, you can see Diedorf nestled in the valley with the surrounding mountain ranges. The Diedorf district covers 961 hectares.

The Catholic parish church "Sankt Alban" is home to one of the most valuable art monuments in the Eichsfeld region, the "Holy Sepulchre". It depicts the burial of the crucified Jesus and was created in 1501. 

A beautiful eye-catcher in the middle of the village is the raised green with its old lime trees. It was the village's meeting place. Two stone crosses can be seen on the west side of the Anger. The Anger is said to have been used as a meeting place, marketplace and court since the 9th century.

From the middle of the 18th century, Diedorf developed steadily through wool combing, wool weaving, cigar production and the hosiery industry.