This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. If an article link referred you here, you might want to go back and fix it to point directly to the intended page.
The counts of Dillingen ruled from the 10th to the 13th century, then (1258) the territory was turned over to the Prince Bishops of Augsburg, who gained several villages for their clerical state, hence subdividing the region into several patches, which were dissolved in the early 19th century.
The district was established in 1972 by merging the former district of Dillingen (which had existed since 1804) with the western half of the former district of Wertingen.
The city of Dillingen lost its status as a district-free city and became the capital of the newly established district.