St. Paul Square is a National Register Historic District also known as the Southern Pacific Depot Historic District. Located on land once farmed by the Mission San Antonio de Valero (the Alamo) in the 18th century, the district was connected to San Antonio by a Spanish road laid out in 1805, now called East Commerce Street.

Sparsely developed in the early 19th century, the area grew significantly with the arrival of the railroad in 1877 and the street car system down East Commerce Street in the 1890s. In 1902, the Southern Pacific Passenger Depot (Sunset Station) was built. The opening of the depot was a catalyst for commercial development, and its Mission Revival style strongly influenced architecture in area. This influence can be seen in the stucco surface and prominent curvilinear parapets of many of the buildings. Most of the existing commercial structures were built during this period with the majority of businesses focused on the theme of transportation.

Although racially mixed from its earliest days, the area became a flourishing African-American community of restaurants, hotels, retails stores, boarding houses, and professional offices by the mid-20th century.

St. Paul Square reached its peak during World War II and the Korean War, despite segregation. However, the rise of automobile traffic and the construction of IH-37 brought about a decline in the 1960s through the 1970s.

Today, the area has experienced a rebirth as an entertainment district with the restoration of many of the historic buildings, new residential construction and the introduction of several dining and entertainment concepts.