Traditionally, these differences were presented as an ethnic division between Irish Gaels and Old English; in 1692, Jacobite historian Charles Kelly claimed Tyrconnell fatally weakened the cause by his opposition to the Gaels. There is some truth in this, particularly as Parliament failed to address compensation for estates confiscated prior to 1641, much of it from Gaelic landowners in Ulster. Modern historians argue differences were based primarily on economics, although those who benefitted from the 1662 Settlement were mostly Old English, those who had not, mostly Gaelic.