[1] The reservoir, also known as Lake Manicouagan, lies within the remnant of an ancient eroded impact crater (astrobleme).

The river's name is believed to come from a Montagnais name meaning "Place where Tree Bark is Found".

However the Innu of Betsiamites call it Menukuanistuk Shipu, meaning "River of the Cup".

In June 1664, Jesuit Henri Nouvel was the first missionary to travel upstream of the "Grand Manikouaganistikou River that the French call rivière Noire because of its depth".

[3] In the early 1950s, the Manicouagan River attracted Hydro-Québec's attention for hydro-electric development because of the deep and fast running waters.