Hi,
One historical event solar physicists talk about a lot is the Carrington Event in 1859. This is the first solar flare observed by humans. It was also one of the most powerful solar events that we have recorded and has been used as an example of how strong they can be - the related CME (or maybe CMEs) lead to aurora as close to the equator as the Caribbean and lead to problems with currents flowing through telegraph lines. More info is here:
https://www.nasaspaceflig...ngton-event-warning/ There is a nice timeline of solar physics related events here:
https://www2.hao.ucar.edu...l-timeline-1800-1999 You will notice a lot of our advances come from new kinds of instrumentation. For instance it was only possible to really understand coronal mass ejections (CMEs) because of the coronagraph, which allows us to observe the solar corona in ways we couldn't before.
Terry