President Moktar Ould Daddah of Mauritania is ousted in a bloodless coup d'état.

Moktar Ould Daddah was a Mauritanian politician who served as the country's first President after it gained its independence from France. Moktar served as the country's first Prime Minister from 1957 to 1961 and as its first President of Mauritania, a position he held for 18 years until he was deposed in a military coup d'etat in 1978.

Mauritania, officially the Islamic Republic of Mauritania, is a country in Northwest Africa. It is bordered by the Atlantic Ocean to the west, Western Sahara to the north and northwest, Algeria to the northeast, Mali to the east and southeast, and Senegal to the southwest. By land area Mauritania is the 11th-largest country in Africa and 28th-largest in the world; 90% of its territory is in the Sahara. Most of its population of some 4.3 million lives in the temperate south of the country; roughly a third of the population is concentrated in the capital and largest city, Nouakchott, on the Atlantic coast.

The 1978 Mauritanian coup d'état was a bloodless military coup in Mauritania which took place on 10 July 1978. The coup, led by the Army Chief of Staff, Colonel Mustafa Ould Salek, who commanded a group of junior officers, overthrew President Moktar Ould Daddah, who ruled the country since independence from France in 1960.

July 10 is the 191st day of the year in the Gregorian calendar; 174 days remain until the end of the year.