The LST I was on was named in 1955. Before it had no name, but went by its numbers as did all LSTs until 1955.
Naval History Center:
Amphibious warfare, long considered a minor function by navies, assumed major importance in World War II. An entirely new "family" of ships and craft was developed for the massive landing operations in Europe and the Pacific. Many types of landing ships did not receive "word" names, but were simply known by their hull numbers (LST 806 and LCI(G) 580). Attack cargo ships and attack transports carried landing craft to put cargo and troops ashore on a beachhead. Many of these were named for American counties (Alamance [AKA 75]; Hinsdale [APA 120]). Some early APAs, converted from conventional troopships, kept their former names (Leonard Wood, President Hayes); many AKAs were named for stars (Achernar) or constellations (Cepheus). Dock landing ships, seagoing ships with a large well deck for landing craft or vehicles, bore names of historic sites (Gunston Hall, Rushmore). Modern LSDs are still part of today's Fleet, and carry on this name source (Fort McHenry, Pearl Harbor). After World War II the remaining tank landing ships (LST) were given names of American counties; thus, the hitherto-unnamed LST 819 now became Hampshire County (LST 819).