The area surrounding Nafplio has been inhabited since ancient times, but few signs of this, aside from the walls of the Acronauplia, remain visible. Subsequently, Byzantines, Franks, Venetians, and Turks added to the fortifications. It became a place of considerable importance, and has continued so down to the present day. In the time of the Crusades it first emerges from obscurity. Nafplio was taken in 1212 by French Crusaders of the Principality of Achaea. It became part of the lordship of Argos and Nauplia, which in 1388 was sold to the Republic of Venice, who regarded it as one of their most important places in the Levant. During the subsequent 150 years, the lower city was expanded and fortified, and new fortifications added to Acronauplia.
The Jan Hus Memorial stands at one end of Old Town Square. The huge monument depicts victorious Hussite warriors and Protestants who were forced into exile 200 years after Hus, and a young mother who symbolises national rebirth. The monument was so large that the sculptor designed and built his own villa and studio where the work could be carried out. It was unveiled in 1915 to commemorate the 500th anniversary of Jan Hus' martyrdom. The memorial was designed by Ladislav Šaloun and paid for solely by public donations.
Born in 1369, Hus became an influential religious thinker, philosopher, and reformer in Prague. He was a key predecessor to the Protestant movement of the sixteenth century. In his works he criticized religious moral decay of the Catholic Church. Accordingly, the Czech patriot Hus believed that mass should be given in the vernacular, or local language, rather than in Latin. He was inspired by the teachings of John Wycliffe.