This is a pair of plates from an edition limited to 3000 examples, diameter 9 1/2", blue on cream, issued in the year 1939, "Commemorating the first visit of British reigning sovereigns to these United States", made by Wedgwood Etruria, "exclusively for W.H. Plummer & Co., New York". One example is hand numbered 261, the other hand numbered 507. That was the year of the New York World's Fair, so I believe it likely there was some relationship to them being in New York that year, as war clouds appeared on the horizon. The royal couple, George VI and the mother of the young Queen Elizabeth-to be (referred to in modern times as the "Queen Mother"), also visited Canada on that visit. The plates are in generally very good condition with some slight glaze crazing, and there is some foreign matter adhering in a few places, though, no chips are present. See the foreign matter in a few photos, some green and some cream color matching the plate surface. I have not tried too hard to remove it but some or all might come off with some careful effort.
Wedgwood PAIR Elizabeth and George VI 1939 limited edition commemorative plates