Article: The city's population increased more than sixfold during the first half of the 20th century, fed largely by an influx of European, Middle Eastern (Lebanese, Assyrian/Chaldean), and Southern migrants to work in the burgeoning automobile industry. In 1940, Whites were 90.4% of the city's population. Since 1950 the city has seen a major shift in its population to the suburbs. In 1910, fewer than 6,000 blacks called the city home; in 1930 more than 120,000 blacks lived in Detroit. The thousands of African Americans who came to Detroit were part of the Great Migration of the 20th century.

Question: What was the movement of blacks to northern cities called?
Great Migration