Issued on July 1, 1941, under Japanese occupation in Shantung province, this mint never hinged block of four features the Large Character “東山” (Eastern Mountain) overprint applied to the 28 cent olive-green “Martyrs of the Revolution” issue. Originally printed by the Commercial Press Ltd. in Hong Kong, this gravure-printed issue was adapted with regional overprints during wartime postal restructuring. Measuring 23 x 28 mm and perforated variably, the stamps were issued without watermark and are presented here in a bottom-margin imprint block bearing the printer’s full inscription “THE COMMERCIAL PRESS LTD.” and plate marking “AR1.2”. The original design honors revolutionary figures of the early Republic and this overprint denotes regional usage control under occupation authorities. The block remains in pristine MNH condition, with sharp overprints, fresh gum, and strong centering. A rare positional piece reflecting the complex philatelic and political climate in wartime East China. Scott 6N59. Estimate "$180 – 230"