Popol Vuh makes reference to shields (pokob') among the Maya.
Popol Vuh: The Definitive Edition of the Mayan Book of the Dawn of Life and the Glories of Gods and Kings (trans. Dennis Tedlock; New York: Touchstone, 1985), 181
And then they tested themselves. They excelled in the Shield Dance, there at Bearded Place. They did it as a sign of their sovereignty. It was a sign of their fiery splendor and a sign of their greatness.
On ibid., 318, we read:
Shield Dance: this is simply called pokob’, “shield”; it is identified as “an ancient dance” by DB.