Trowbridge Square Historic District, originally known as Village of Spireworth and Mount Pleasant, is a well-preserved 19th-century neighborhood in the Hill section of New Haven, Connecticut.

Roughly bounded by Columbus, Howard, and Union Avenues, and Church Street on the east, the area was laid out in 1830 and developed as a working-class neighborhood.

The idea was picked up in 1830 by Simeon Jocelyn and Isaac Thompson, who purchased the land, laid out the street grid, and dubbed the new development "Spireworth".

Jocelyn, a successful businessman and real estate developer, sought to create "a harmonious community in which the city's poor and disadvantaged, a high proportion of whom were blacks, could achieve spiritual, moral and (hopefully) economic betterment.

"[2] Development remained slow until the 1850s, when Thomas Trowbridge funded improvements to the park (including its fence) and spearheaded construction of the church.