Complex sentence: In the following year Ginkel captured Athlone, owing to the carelessness of the Jacobite general, St-Ruth; and on 12 July, 1691, the last great battle of the war was fought at Aughrim.
Split into simpler sentences: In the following year Ginkel captured Athlone, owing to the carelessness of the Jacobite general, St-Ruth. On 12 July, 1691, the last great battle of the war was fought at Aughrim.