Matilda of Hainaut, also known as Maud and Mahaut, was Princess of Achaea from 1316 to 1321. She was the only child of Isabella of Villehardouin and Florent of Hainaut, co-rulers of Achaea 1289–1297. After Florent's death in 1297, Isabella continued to rule alone until she remarried to Philip of Savoy in 1300. Per arrangements made with King Charles II of Naples, Isabella was not allowed to marry without his consent and after Philip failed to adequately participate in the king's campaigns against Epirus, Charles in 1307 revoked their rights to Achaea. Matilda, just fourteen years old, tried to press her claim as their heir but was refused by the bailiff Nicholas III of Saint Omer, who instead chose to wait for orders from Naples. Shortly thereafter, Charles appointed his favorite son, Philip of Taranto as the new Prince of Achaea.

The Prince of Achaea was the ruler of the Principality of Achaea, one of the crusader states founded in Greece in the aftermath of the Fourth Crusade (1202–1204). The principality witnessed various overlords during its more than two centuries of existence, initially, Achaea was a vassal state of the Kingdom of Thessalonica under Boniface I of house Montferrat, then of the Latin Empire of Constantinople under the houses of Flanders-Courtenay, which had supplanted the Byzantine Empire, and later of the Angevin Kingdom of Naples. During the Angevin period, the princes were often absent, represented in the Principality by their baillis, who governed in their name. After 1404 the principality became sovereign as the Genoese Centurione II Zaccaria bought from the Neapolitan crown the princely rights.