There are three explanations for the name of Aradeo, and the comune, when it gave itself a coat of arms in 1963, chose one: the arms allude to Ara Dei, the altar of God, following the reading of the historian Giacomo Arditi. The other two lead elsewhere. The linguist Gerhard Rohlfs traced it back to an Ἀραταῖον, that is, the place dedicated to the Achaean general Aratos, and cited as its oldest form a Greek phrase of 1149 mentioning the archpriest of Aradeo. Professor Gino Pisanò, more recently, proposes the Greek Charadreon, «place furrowed by torrents», and the explanation holds well, because beneath this karst land the streams really do run, hidden. Pisanò found and translated two parchments, the one of 1149 and another slightly later, which show beyond escape how Greek Aradeo was: Greek names of priests and of churches, and among them the Byzantine poet Drosos of Aradeo, whose manuscripts have been found in Paris. Between the thirteenth and fourteenth centuries, thanks to Drosos himself, a school of philosophy worked here.
Feudal history begins in 1191, when Tancred of Lecce enfeoffed the hamlet to the Montefusco; then Aradeo passed into the county of Soleto, to the Angevins, to the Orsini del Balzo and for a while under the monastery of Santa Caterina d'Alessandria of Galatina. In 1485 king Ferdinand I of Naples assigned the fief to Giovanni Castriota, son of Giorgio Castriota Skanderbeg, together with Galatina and Soleto and with the title of duke and count: the same surname that, four centuries later, would reappear a few kilometres from here, at Ruffano. Of the church of the Annunziata one detail is worth telling: built in the first half of the fifteenth century, towards the end of the eighteenth it collapsed entirely because of the rising damp that was undermining its load-bearing walls, and of the whole building one thing alone survived undamaged, the high altar of 1570, carved in Lecce stone with twisted columns and a small oval canvas at its centre. The church was rebuilt around 1800, its foundations reinforced in 1850 and finished in 1879 with the domed presbytery. Not far off is the chapel of San Nicola di Myra, raised for a grace received between the sixteenth and seventeenth centuries: it is so small that it does not even have a door.