Complex sentence: Guthrum withdrew his army from the western borders facing Alfred's territory and moved eastward before eventually settling in the Kingdom of Guthrum in East Anglia in 879.He would live out the remainder of his life there until his death in 890.
Split into simpler sentences: Guthrum withdrew his army from the western borders facing Alfred's territory and moved eastward before eventually settling in the Kingdom of Guthrum in East Anglia in 879. He lived out the remainder of his life there until his death in 890.