Answer:
1000 bce when the Greek alphabet first popped up, and it is directly or indirectly linked to all European alphabets that exist today.
The Gothic alphabet, created by Ulfilas in 4th century AD, the Glagolitic alphabet, created by one monk known as Saint Cyril in the 9th century, and the modern Cyrillic and Latin alphabet are all ultimately derived from the Greek alphabet.
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