Before revision: Due to recent discoveries of inscriptions at Halicarnassus dated to about Herodotus' time, it is now know that the Ionic dialect was used in Halicarnassus in some official documents, so there is no need to assume (like the Suda) that he must have learned the dialect elsewhere.
After revision: Due to recent discoveries of inscriptions at Halicarnassus dated to about Herodotus' time, it is now known that the Ionic dialect was used in Halicarnassus in some official documents, so there is no need to assume (like the Suda) that he must have learned the dialect elsewhere.