Complex sentence: The Ceres stamps were the first issued after the proclamation of the Portuguese Republic, superseding stamps figuring king Manuel II that had been overprinted with the word "Republica" 1910-1911.
Split into simpler sentences: The Ceres stamps are the first issued during after the proclamation of the Portuguese Republic. They replaced stamps figuring king Manuel II that were overprinted with the word "Republica" 1910-1911.