Cognomen Gastu (Gastu 
) , in the world, is a rare family name. The last name Gastu is characteristic of France, where it is a very rare surname, and India, where it is an extremely rare surname. Much less frequently, Gastu is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gastu | Argentina, India, France |
| gaudérique gastu French general, FR (b. 1802) |
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| françois gastu French politician (1834-1908), FR (b. 1834) |
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