Complex sentence: However, when Edward's army approached and camped nearby at Badbury Rings, he was unable to gain sufficient support to meet them in battle, and so, leaving behind his wife, he fled to the Danes of Northumbria.
Split into simpler sentences: However, when Edward's army approached and camped nearby at Badbury Rings, he was unable to gain sufficient support to meet them in battle. Leaving behind his wife, he fled to the Danes of Northumbria.