Complex sentence: One of the terms of the surrender was that Guthrum convert to Christianity; and three weeks later the Danish king and 29 of his chief men were baptised at Alfred's court at Aller, near Athelney, with Alfred receiving Guthrum as his spiritual son.
Split into simpler sentences: One of the terms of the surrender was that Guthrum convert to Christianity. Three weeks later the Danish king and 29 of his chief men were baptised at Alfred's court at Aller, near Athelney, with Alfred receiving Guthrum as his spiritual son.