At https://wattsupwiththat.com/2019/03/12/monster-solar-storm-that-hit-eart… … scientists have found evidence of a large blast of radiation that struck the Earth in 660BC. Solar proton particles were involved and it has been compared to the AD775/6 event. Some Japanese scientists blamed the latter on perhaps the Earth passing through the coma of a comet, an idea that received no traction from other scientists. Both events were significantly more powerful than the 19th century Carrington event.
The comments section is well worth a browse as various ideas are given an airing. They include a short discussion on whether it could, or not, have affected C14 dating methodology. I can't think of anything in particular that is recorded from the era that might have a connection – but would auroral phenomena at lower latitudes have been that remarkable. The Chinese might come up with something as they recorded heavenly portents. Interestingly, it is 50 years later that we had a C14 anomaly from the ruins of Nineveh (around 610BC). Three skeletons were C14 dated between 150 and 180 years too old to the 8th century BC rather than the early 7th century BC). There are also problems in early to mid Iron Age Britain – an occupation downturn (or dark age) of sorts, not fully understood or addressed. The date also coincides with the first calibration curve – where it diverged from the raw C14 data.
Another point to bear in mind is that the later 640s BC witnessed a population collapse in the Assyrian empire (and the beginning of its downfall) closely followed by an eruption of Scythians on the northern border, an idependence movement in Egypt and in Judah (of Josiah) etc. None of this need have a connection with an increase in solar radiation as people at that time did not use modern technology such as GPS and smart phones. How would it have affected the people living at that time – bigly, or hardly at all?
To read the full article go to https://www.pnas.org/content/early/2019/03/05/1815725116 … or https://doi.org/10.1073/pnas.1815725116