Surgeon William Robert Douglas Blackwood (May 12, 1838 – April 26, 1922) was an Irish soldier who fought in the American Civil War.

Blackwood received the United States' highest award for bravery during combat, the Medal of Honor, for his action during the Third Battle of Petersburg in Virginia on April 2, 1865.

He immigrated to the United States and studied medicine at the University of Pennsylvania Medical School in June 1859, completed his course work in 1861, wrote his thesis on gastro-intestinal digestion, and graduated in 1862.

[5] During the Third Battle of Petersburg when Fort Mahone was being attacked, Blackwood assisted several seriously wounded soldiers from the battlefield.

[5] Removed severely wounded officers and soldiers from the field while under a heavy fire from the enemy, exposing himself beyond the call of duty, thus furnishing an example of most distinguished gallantry.