The “cross of Santiago”, or “cross of St. James”, is the insignia of the Knights of Santiago, an Iberian order founded in 1170 [Spada’s Onori e Glorie: Sovrano Militare Ordine, p.61]. It is also blazoned a cruz espada (“sword-cross”) in Iberian armory; it’s considered a highly ornamental form of the cross flory fitchy. The Portuguese and Spanish had slightly different forms; the illustration shows a 16th C. Spanish form.
Ximena Yannez de Talavera bears: Per chevron azure and vert, three crosses of Santiago Or.
Cristóbal Vázquez de Narriahondo bears: Per pale azure and argent, a cross of Santiago counterchanged.