Laetus was born at Teggiano, near Salerno, the illegitimate scion of the princely house of Sanseverino, the German historian Ludwig von Pastor reported.
About this time he founded an academy (Accademia Romana), the members of which adopted Greek and Latin names,[2][3] and met at the house of Laetus on the Quirinal, which was filled with fragments and inscriptions and Roman coins collected by this early antiquarian, to discuss classical questions;[4] they celebrated the birthday of Romulus.
[3] Bartolomeo Platina and Filippo Buonaccorsi were among the most distinguished members of the circle, which also included Giovanni Sulpizio da Veroli, the editor of the first printed De architectura of Vitruvius and organizer of the first production of a Senecan tragedy mounted since Antiquity.
Laetus, who was still in Venice at the time the supposed conspiracy was discovered, was sent back to Rome, imprisoned and put to the torture, but refused to plead guilty to the charges of infidelity and immorality.
Laetus, who has been called the first head of a philological school, was extraordinarily successful as a teacher; he said that he expected, like Socrates and Christ, to live on through his pupils, some of whom were many of the most famous scholars of the period.