Path Five: 1521-1699 AD
This period of the legend begins with the earnest (and arguably successful) search by a Portuguese Embassy in 1520 to locate Prester John in Ethiopia, features minor appearances in literary texts (many of which reflect the neo-Chivalric revival of the late 1580s through the 1590s), and terminates in an age of skepticism about the legend that closes the 18th century.
During this era, Prester John was mainly identified with Africa-- particularly Ethiopia. Through the sixteenth century, this identification became common for most European world maps. On a 1540 map by Munster, for example, the capital city of the kingdom of Prester John is situated in "Hamarich" (may be present day Hamar).
As Niayesh argues (p. 164), here we see a transformation of the figure of Prester John from belated European savior "into the prototype of the eastern ruler who is to be overcome and no longer sought after as an ally." While Niayesh's comment accurately describes the developments of some of the writing on Prester John (especially in fiction), his kingdom remained for others still a real physical target (or at least a useful rhetorical ally).
Given Portugal's aggressive missions to Africa in general and Ethiopia in particular, the era is dominated by Portuguese thought and writing, but other European countries were still using the figure of Prester John as a means of negotiating their own power and understanding of the world. Several English writers, including George Abbot, found a spiritual ally in Prester John by emphasizing the imaginary rulers resistance to Catholicism. Others, such as Edward Webbe, continued to promote the same story that had been told since Mandeville.
It can be argued that this era ended in the year 1633, when Ethiopia closes its borders to Europeans after the expulsions of the Jesuits by Emperor Fasilides, yet, as Brewer (p. 273) points out, there are hundreds (if not thousands) of texts from the sixteenth through eighteenth centuries that contain some comment associating Prester John with Ethiopia.
While European travel to Ethiopia may have ended in the first half of the seventeenth century, the texts and tales that circulated for the rest of the century almost entirely reflect the narratives that first established this era, most due to Portuguese travel.