Complex sentence: The Armada under the command of the Adelantado, Martín de Padilla was gathered at Lisbon, Vigo and Seville and set off; but before it had left Spanish waters storms struck the fleet in the Bay of Biscay near Cape Finisterre.
Split into simpler sentences: The Armada under the command of the Adelantado, Martín de Padilla was gathered at Lisbon, Vigo and Seville and set off. Before it had left Spanish waters storms struck the fleet in the Bay of Biscay near Cape Finisterre.