Complex sentence: Until the Inclosure Acts which came into force in England in the eighteenth century there had been little need for horses to jump fences routinely, but with this act of parliament came new challenges for those who followed fox hounds.
Split into simpler sentences: Until the Inclosure Acts which came into force in England in the eighteenth century there had been little need for horses to routinely jump fences. But with this act of parliament came new challenges for those who followed fox hounds.