William Parvin Brobson (1786–1849)^[1] was a lawyer, Delaware state representative, newspaper editor, and railroad executive.

He was admitted to the Delaware bar in 1810.^[2]

He was several times elected to the Delaware House of Representatives as a delegate from New Castle County, holding office in 1820–21, 1821–22, and 1826–27.

In 1825, he married Elizabeth Tatnall Starr,^[1] granddaughter^[3][4] of prominent Delaware businessman Joseph Tatnall.

Around 1834, he became the editor of the Delaware Journal (sometimes referred to the Delaware State Journal), a Wilmington, Delaware, newspaper founded in 1831.^[5] Historian John Thomas Scharf called him "a talented Wilmington lawyer of that day, and a clear, vigorous writer."^[2]

In 1835, Brobson became the secretary to the board of directors of the Wilmington and Susquehanna Railroad, one of the four railroads that built the first rail link from Philadelphia to Baltimore.^[1] In 1838, he was assistant secretary of the merged Philadelphia, Wilmington, and Baltimore Railroad. His service as an early railroad executive is noted on the 1839 Newkirk Viaduct Monument. Today, the right-of-way is owned by Amtrak and forms part of the Northeast Corridor.

In 1838, he became the first cashier for the Union Bank of Delaware.^[1]