The Mycenaean civilization followed the Minoan civilization in Greece. The Mycenaeans used a script called Linear B which descended from an undeciphered earlier script called Linear A. Like the script used in the Indus-Saraswati civilization, this was an unknown script representing an unknown language and that made deciphering it a difficult problem. Despite that the script was deciphered and the credit for that is attributed to an English architect named Michael Ventris.
According to an article, Ventris would not have made the breakthrough, if not for the work of an American classical scholar named Alice Kober.
In the search for clues, Kober learnt a whole host of languages – from Egyptian to Akkadian to Sumerian and Sanskrit. But Kober was rigorous in her work – refusing to speculate on what the language was, or what the sounds of the symbols might be. Instead, she set out to record the frequency of every symbol in the tablets, both in general, and then in every position within a word. She also recorded the frequency of every character in juxtaposition to that of every other character. It was a mammoth task, performed without the aid of computers. In addition, during the years surrounding World War II, writing materials were hard to come by. Kober recorded her detailed analysis on index cards, which she made from the backs of old greetings cards, library checkout slips, and the inside covers of examination books. By hand, she painstakingly cut more than 180,000 tiny index cards, using cigarette cartons as her filing system.Kober’s monumental effort paid off. She spotted groups of symbols that appeared throughout the inscriptions – groups that would start the same, but end in consistently different ways. That was the breakthrough. Kober now knew that Linear B was an inflected language, with word endings that shifted according to use – like Latin, or German or Spanish.[Alice Kober: Unsung heroine who helped decode Linear B]