Neil is an archaeologist, historian, author and broadcaster, His television debut came in 2002 with BBC Two's Two Men in a Trench, which featured Neil visiting historic British battlefields and recreating the battle situation using state of the art archaeological techniques. In addition to the TV series, Oliver co-wrote the two accompanying books.

In 2005, he starred in the Channel 4 documentary, Not Forgotten and wrote a tie-in book. Neil then became the archaeological and social history expert on Coast, then in the next series he replaced Nicholas Crane as the show's main presenter and remained as such for the third series.
2006 saw Neil star in two more documentary series, Channel 4's The Face of Britain and BBC Two's Scotland's History: The Top Ten. As well as this, in August 2006 he appeared on the special "Big Royal Dig" edition of Channel 4's Time Team, in which he presented a dig at Holyrood House.

Neil was a contributor to BBC One's The One Show in the summer of 2007. That year he also appeared as one of the presenters of BBC Two series The History Detectives.

Neil is to present a new ten-part series, A History of Scotland, to be broadcast starting in November 2008 on BBC Two Scotland and later throughout the UK.