Complex sentence: There were ironworks here in Edward the Confessor's reign in the 11th century, when Gretton was a royal manor, and the industry came to the fore again from 1881 to 1980, providing ore for Corby's steel works.
Split into simpler sentences: There were ironworks here in Edward the Confessor's reign in the 11th century, when Gretton was a royal manor. The industry came to the fore again from 1881 to 1980, providing ore for Corby's steel works.