From Wookiepedia, which is unspeakably awesome:
"Behind the scenes
Many of the Mandalorians on Dxun (in Star Wars: Knights of the Old Republic II: The Sith Lords) speak with a New Zealand accent, following Temuera Morrison. By the same token, Fett and all the Mandalorian characters in Legacy of the Force novels’ audio adaptations are given approximate New Zealand accents by reader Marc Thompson.
Mandalorians have a well-developed complex culture and were the first species/people in Star Wars to have their own fully-constructed language. Most of those elements were created and developed by Karen Traviss. Their idiomatic character and culture have their own fan following called Fandalorians.
Boba Fett—the first named Mandalorian—was not going to be a Mandalorian at all, but simply wear the armor. This idea might have been adapted with Jodo Kast.
In the Star Wars Episode V: The Empire Strikes Back novelization, the Mandalorians are referred to as warriors wiped out by Jedi during the Clone Wars. While many Mandalorians were killed, they were not completely destroyed, nor did the massacre occur during the Clone Wars, but rather, a decade previous.
The name “Mandalorian” may come from the Latin word “Mando,” meaning “order”. In Sasha ot Sulem’s dialect which could be related to Mando’a, the word ‘Mandalorian’ is translated as ‘Manlorey’."
(In the voice of that corporate supervisor guy from Office Space : ) I am – I’m a FANDALORIAN!"