Napoleon entered Spain with a well-appointed army, and soon, through strategy and well-directed force, gained possession of the important fortresses of the Peninsula; seizing in this way the strategic routes and important geographical points, he was enabled to retain possession of the country for eight years, in spite of the numerous forces arrayed against him, the absence of himself and his best generals in Germany, and the great inefficiency of Joseph and of many of his generals.

These fortifications were old, and of strength inferior to modern works of defence, but it required years and the expenditure of millions in blood and treasure to expel from the country those who had possession of them.
For the first five years of this war the English struggled with a most imperfect army organization.[37] When "the first serious siege," says Napier, was undertaken by the British army, "to the discredit of the English government, no army was ever so ill provided with the means of prosecuting such an enterprise.

The engineer officers were exceedingly zealous; and many of them were well versed in the theory of their business.

But the ablest trembled when reflecting on their utter destitution of all that belonged to real service.

Without a corps of sappers and miners, without a single private who knew how to carry on an approach under fire, they were compelled to attack fortresses defended by the most warlike, practised, and scientific troops of the age." [Footnote 37: In a letter dated February 11th, 1812, Wellington wrote to the Secretary of State as follows:--"I would beg leave to suggest to your lordship the expediency of adding to the engineer establishment a corps of sappers and miners.