Family name Castellanus (Castillan 
, Castellan 
, Castelan ) , across the world, is a common cognomen. The last name Castellanus is characteristic of Mexico, where it is quite a common surname, Italy, where it is quite a rare surname, and Guatemala. Not in comparison with a country's population, it is commonest in Mexico, Italy, and Brazil. Much less frequently, Castellanus is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Castillan | United States, France, Philippines, Democratic Republic of the Congo, Canada |
| Castellan, Castelan | United States, France, Mexico, Italy, Brazil |
| Castellanus | United States |
Castigliano, and Chatelaine
| vincentius castellanus artist |
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