Speculation was rife that Campo would decide to return to Spain once his contract expired following the news a number of clubs in La Liga were starting to show an interest in him.
Boss Sam Allardyce was keen to secure his future though and Wanderers officials jetted out to Spain to make sure the talented playmaker put pen-to-paper.
Meanwhile, Southend United have 'strengthened' their squad with the signing of Michael Ricketts as he prepares for life in the Championship.
Chief executive Geoffrey King told the club's official website, "Shaun Goater proved last year what an experienced face can bring to the side and we hope Michael will prove just as successful."
The 27-year-old started his career with Walsall but made his name at Bolton, scoring 24 goals in the 2000-01 campaign.