Why did the Harlem Renaissance start in Harlem?

From the video in class we learned that Harlem in New York City was a center of the new jazz music that was mostly performed by blacks. This area represents a Renaissance of new art and literary forms that gave birth to a "new negro", where black people became proud of their race. Why is this new culture specifically tied to Harlem?

The Great Migration
Before 1890, 90% of the black population lived in the South. The Restoration in the south did not bring them safety and security. They could not own land, and most became stuck as sharecroppers in an endless cycle in debt. Further, disfranchisement and the Jim Crow laws reinforced inequality. These pressures led many to hope for a new life up north. The big cities in the north also pulled their interests, with numerous industrial jobs and factory owners seeking for cheap labor. Starting in about 1890, large numbers of black people migrated north for better lives.

In the north, racism was still present. New migrants were accused of lowering wages and taking up the jobs of white laboers. As a result, they found themsevles segregated by practive in urban slums. The largest of them was Harlem, which was the part of Manhattan Island north of Central Park and east of 8th Avenue. As more blacks moved in, white property owners wanted to move out and began to sell their property at low prices. By 1914, there were around fifty thousand blacks living in Harlem



Harlem
Becuase of its large and expanding size, Harlem became the focus of African American literature, art, music, and theater. Its night clubs, music halls, and jazz joints became the center of New York nightlife in the 1920s. In this community rose many artists, musicians, writers, and leaders. Prolific writers included Langston Hughes, Claude McKay, Jean Toomer, and Zora Nealle Hurston. Jazz played a huge part, as artists such as Duke Ellington, Bessie Smith, Billie Holiday, and Louis Armstrong drew huge audiences in, white and black. 

It is also important to note that while Harlem was central to the new culture, it served more as an anchor for the movement than its sole location. In reality, it was connected with the reset of the US, as well as other parts of the world. Most of the famous people of Harlem were also immigrants to New York. Yet, Harlem symbolized the progress of black people in this new age.

Sources:
http://www.ushistory.org/us/46e.asp
http://www.humanitiestexas.org/news/articles/harlem-renaissance-what-was-it-and-why-does-it-matter