Complex sentence: The house was destroyed by the local IRA unit during the Irish War of Independence in 1920 due to rumours that it was going to be used by the Black and Tans as an infirmary.
Split into simpler sentences: The house was destroyed by the local IRA unit during the Irish War of Independence in 1920. Rumour had it that it was going to be used by the Black and Tans as an infirmary.