According to Herodotus, the expression phoinikeia grammata means ‘Phoenician letters’ and refers to the Phoenician origins of the Greek alphabet. This account has found general acceptance, but it is not the only interpretation possible and other theories circulated in antiquity. The adjective φοῖνιξ does not only mean ‘Phoenician’; it can also refer to a palm tree or the colour red. This article argues that the expression phoinikeia grammata did not originally refer to the alphabet, but to Linear B writing on palm leaves, as already suggested by Frederick Ahl. It is shown that the account of Herodotus is the result of a ‘learned reinterpretation’, triggered by the ambiguity of the word φοῖνιξ. The new understanding of phoinikeia grammata proposeds here has some important consequences: it implies that Linear B, as has long been suspected, was primarily written on palm leaves (hence ‘palm-leaf writing’) and that in classical antiquity there was at least a limited historical awareness of the existence of pre-alphabetic writing systems in the Aegean. This paper adduces additional evidence to substantiate these claims. Lastly, a case will be made that Herodotus’ incorrect reinterpretation has led to the ‘Phoenicianization’ of Cadmus, who was originally a Greek hero.