The appointment was made by Graham Duff (pictured), the Universal McCann EMEA president, as part of a global restructure at the network.
King has spent the past seven years as the manager of Universal McCann in the Czech Republic. He will now take charge of the network's Polish, Hungarian, Czech, Slovakian, Romania, Balkan, Baltic, Russian and Ukrainian markets.
Duff said: "It is essential for me to have a strong structure and support from my management team in the region. I am delighted to bring such an energetic and proven operator as King into this role."