Bertholdt Hoover was an Eldia and one of the Marley Warriors. He is from Liberio concentration and possesses the power of the Titan, making him one of the greatest threats to humanity in the city wall. In the year 845, he infiltrated Paradis Island with Reiner Braun, Annie Leonhart, and Marcel Galliard as part of his campaign to take back the Titan of the Water Father.