Complex sentence: It is claimed that he was present at the Battle of Seneffe that year, and that he rescued the young Prince when his horse fell in marshy ground although there is little evidence to support, or disprove this claim.
Split into simpler sentences: It is claimed that he was present at the Battle of Seneffe that year, and rescued the young Prince when his horse fell in marshy ground. There is little evidence to support, or disprove this claim.