This name is of Latin (Roman) origin and has two possible meanings. The first is as a descriptive personal term of endearment for one of mild and peaceful temperament, the second implies a dweller by the main street or market square of the town. If the second is correct then the original spelling was probably 'di placidi' (of the square) although the modern spelling would be Del Piazo. The first recorded spelling of the family name is shown to be that of The Countes Placidi. which was dated C. 1680, Siena, Tuscany, Italy. during the reign of Pope Innocent X1 1676 - 1689. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.