Complex sentence: There is no information about its future fate after their foundation, perhaps it was destroyed by the Thracians a few years after the founding, or later, in the year 437 BC, The colony founded Amphipolis.
Split into simpler sentences: There is no information about its future fate after their foundation; perhaps it was destroyed by the Thracians. A few years after the founding, or later, in the year 437 BC, the colony founded Amphipolis.