Sir William Young was born on September 8, 1799, in Falkirk, Scotland.

He was a businessman, lawyer, and politician. In 1813, he graduated from the University of Glasgow. He emigrated to Halifax, Nova Scotia, with his parents in 1814 and helped establish his father’s wholesale dry goods business, John Young and Company. He acted as his agent in Halifax and New York. In 1815, he formed a partnership with James Cogswell to operate an auction and commission business that lasted until 1820. In 1825, he became an attorney and started practicing law in Halifax after passing the bar in 1826. In 1834, with his brother, George Renny Young (1802-1853), they established an insurance business that lasted into the 1850s. In 1836, Young was elected to the Nova Scotia House of Assembly. When responsible government was instituted in 1848, he became Speaker of the Assembly. In 1854, he was elected the 2nd Premier of Nova Scotia and served until 1857. In 1860, he was appointed Nova Scotia's Chief Justice, serving until his retirement in 1881. In 1869, he became a Knight Bachelor and received an honorary degree from Queen's College, Kingston. Young contributed financially to Dalhousie College and served as chairman of its Board of Governors for thirty-six years (1848-1884).

In 1830, he married Anne Tobin (1805–1883). He died on May 8, 1887, in Halifax, Nova Scotia.