Because the ninth square was located closest to the colony's harbor, it was the first to develop a significant commercial presence.

In the 1820s, the Farmington Canal was routed near the district, spurring further commercial development.

The conversion of the canal right-of-way to railroad use intensified the area's commercial development in the second half of the 19th century.

The area declined after World War II, but has been spared from destruction in urban renewal activities of the mid-20th century.

[2] The Ninth Square has been at the center of New Haven's cultural renaissance, densification and renewal over the last[which?]