Complex sentence: He took ill shortly after this, on 6 December; by some accounts this was a nervous collapse caused by the defeat, and he may have died from the grief, although some historians consider that it may just have been an ordinary fever.
Split into simpler sentences: He took ill shortly after this, on 6 December; by some accounts this was a nervous collapse caused by the defeat, and he may have died from the grief. Although some historians consider that it may just have been an ordinary fever.