ولاية نابل
Messadi was born in Tazarka, Nabeul Governorate, Tunisia. His education began in the village Quranic school, where he memorized part of the Qur’an before starting primary school in Qirba. He then completed high school in the Sadiqi Institute in Tunis in 1933. In the same year, he enrolled at the Sorbonne University in Paris to study Arabic language and literature. He graduated in 1936, then began preparing his first PhD dissertation on Abu Nuwas as well as a second on the rhythm of classical Arabic poetry. He finished the first dissertation but the Second World War prevented him from defending it. The second was later published in Arabic and French. He started teaching at the Islamic Studies center in Paris in 1952.