Educated at the independent day school King's College School, Urban continued his education at the London School of Economics. Upon graduation, he served in the Army, for nine months as a regular officer in the Royal Tank Regiment on a Short Service Limited Commission and, subsequently, four years in the Territorial Army.

Initially, he entered broadcasting behind the camera on a variety of BBC news programs. Since then, he has been the defence correspondent of The Independent and Middle East correspondent for BBC News during which he was an embedded reporter, first with British and then U.S. troops. In his years on Newsnight, he has reported on many of the most compelling foreign news stories in the past two decades: the Gulf War; the attempted coup d'état in Moscow; 1993 events in Moscow; Bosnian War; Middle East peace process; the War in Kosovo; and the recent US military campaigns in War in Afghanistan and War in Iraq.

His most recent book, The SAS's secret war: The book the MoD doesn't want you to read, will be released in February 2010 by Little, Brown, and is, according to early reviews, "a heart-stoppingly vivid account of the Iraq conflict," particularly the so-called "Black Ops" efforts at counter-terrorism.

In 2009 he received a Peace Through Media Award from the International Council for Press and Broadcasting.

In 2001, Urban published his first book on the Napoleonic Wars in the Iberian Peninsula. His study of George Scovell, in The Man Who Broke Napoleon's Codes: The Story of George Scovell established him as a narrative historian who could effectively weave together first-hand accounts of the war without losing grip on the over-all story. His second narrative history, Rifles: Six Years with Wellington's Legendary Sharpshooters, published in 2003, continues the story of the Iberian campaign, through the history of the famed 95th Rifles. His study of the Royal Welch Fusiliers followed the same pattern as his earlier successes, combining first-hand accounts with an overarching narrative.