He wrote books about historic events, such as the 1954 FIFA World Cup, and RAF terrorism.

Four of his novels were translated into English, including The Pears of Ribbeck and Portrait of the Mother as a Young Woman.

[9] In the citation for the 2011 Büchner Prize, Delius was described as a "critical, resourceful and inventive observer" ("kritischer, findiger und erfinderischer Beobachter") who dealt with Germans in the 20th century "from the prehistory of the Nazi era to the time of partition and the immediate present" ("von der Vorgeschichte der NS-Zeit über die Zeit der Teilung bis in die unmittelbare Gegenwart").

[7] Der Spaziergang von Rostock nach Syrakus [de] (The stroll from Rostock to Syracuse) is a 1995 story with a protagonist from East Germany who dreams of walking to Italy like Johann Gottfried Seume in the 19th century.

[20] In Der Sonntag, an dem ich Weltmeister wurde, he wrote about the German victory in association football at the 1954 FIFA World Cup, and his Deutscher Herbst trilogy was about the RAF terrorism.