875 (DCCCLXXV) was a common year starting on Saturday of the Julian calendar, the 875th year of the Common Era (CE) and Anno Domini (AD) designations, the 875th year of the 1st millennium, the 75th year of the 9th century, and the 6th year of the 870s decade. As of the start of 875, the Gregorian calendar was 4 days ahead of the Julian calendar, which was the dominant calendar of the time.

• December 29 – Charles the Bald, king of West Francia, is crowned emperor.
• The Danes capture Lindisfarne and arrive in Cambridge.
• Harald Fairhair subdues the rovers on Orkney and Shetland and adds them to his kingdom.

• In Champa, in the central region of what is now Vietnam, King Indravarman II founds a new dynasty at Indrapura (Quang Nam). He starts a building program featuring the Dong Duong Style of Cham art.

• The construction of Mosque of Uqba, Kairouan, Tunisia, is ended.

• Muslim ibn al-Hajjaj Nishapuri Islamic writer

• August 12 – Louis II, Western Emperor
• Amram Gaon, Jewish liturgist
• Abu Muslim, Persian hadith compiler