Johnston replaces Sarah Wood who is now the non-executive chair of Unruly’s board. He will work under News UK chief executive Rebekah Brooks.
The news organisation bought Unruly in 2015 to boost its ad offering with access to the agency’s video marketplace.
On the hire, Brooks said: “Norm's data-driven approach and deep understanding of marketers' requirements will be invaluable to Unruly clients and the wider News Corp business. He's a programmatic pioneer with truly global experience and I'm very much looking forward to working with him as we build on the milestones that Unruly has already achieved.
She added: “I am deeply grateful to Sarah Wood and to her co-founders, Scott Button and Matt Cooke, for their commitment to transforming advertising for the better. They have built Unruly into a scaled and trusted advertising platform and I look forward to Sarah chairing the Unruly board and continuing to bring her passion and vision to the table.”
Robert Thomson, chief executive of News Corp, added that the hire will maximise the group’s “formidable digital advertising capabilities”.
Johnson is credited with working for the first ever digital marketing agency Modern Media and helping to place the first ever banner ad. He’s been with WPP group since 2007.