Santhià and Santià are typically Piedmontese and both very rare, although the first, which is the archaic form of the second, is slightly more widespread, should derive from the name Vercellese Santià. Additions provided by Giovanni Vezzelli Santhià is a surname of the Vercellese from the homonymous name. According to D. Olivieri, Dictionary of Piedmontese toponomics 1965, p. 312 derives from S. Agatha, (comitatus-) S. Agathae, since the end of the century. X.
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