What is the period between 500 c.e. and 1500 known as, and why is it referred to by that name?

In 1519, the explorer Alonso Álvarez de Piñeda became the first European to map the Texas Gulf Coast. ... For the next eight years, Cabeza de Vaca and the remaining survivors would become the first Europeans to view the diversity of the landscape and people of what we now call Texas.