Seiberlich was posted to the destroyer . He spent the rest of World War II on her, participating in the Battle of Salerno, where "Mayo" engaged German tanks, and the Battle of Anzio, where "Mayo" was badly damaged by a naval mine. In 1945, "Mayo" went to the Pacific, and participated in the Battle of Okinawa. Seiberlich was present on "Mayo" in Tokyo Bay for the signing of the Japanese Instrument of Surrender on the in September 1945.