The Spanish Third

With our souls united for the same faith
 Let the blood flow protecting our Kingdom
 The cross from Borgogna, flying in the wind
 Sons of Santiago, our tercios are great
Pikemen squadron, protecting the wings,
The only free men are those without fear.
 Fight for your brothers, die for your kingdom
Live for the peace of this huge empire.
We won't be defeated, if we're captured.
We will only capitulate when we're dead.

(Translation courtesy of this site )

Read about Tercios over here.