Louis chose extension by land. He had married the eldest daughter of
Philip IV., the then reigning king of Spain; and though by the treaty
of marriage she had renounced all claim to her father's inheritance,
it was not difficult to find reasons for disregarding this
stipulation. Technical grounds were found for setting it aside as
regarded certain portions of the Netherlands and Franche Comte, and
negotiations were entered into with the court of Spain to annul it
altogether. The matter was the more important because the male heir to
the throne was so feeble that it was evident that the Austrian line of
Spanish kings would end in him. The desire to put a French prince on
the Spanish throne--either himself, thus inheriting the two crowns,
or else one of his family, thus putting the House of Bourbon in
authority on both sides of the Pyrenees--was the false light which
led Louis astray during the rest of his reign, to the final
destruction of the sea power of France and the impoverishment and
misery of his people. Louis failed to understand that he had to reckon
with all Europe. The direct project on the Spanish throne had to wait
for a vacancy; but he got ready at once to move upon the Spanish
possessions to the east of France.

In order to do this more effectually, he cut off from Spain every
possible ally by skilful diplomatic intrigues, the study of which
would give a useful illustration of strategy in the realm of politics,
but he made two serious mistakes to the injury of the sea power of
France. Portugal had until twenty years before been united to the
crown of Spain, and the claim to it had not been surrendered. Louis
considered that were Spain to regain that kingdom she would be too
strong for him easily to carry out his aims. Among other means of
prevention he promoted a marriage between Charles II. and the Infanta
of Portugal, in consequence of which Portugal ceded to England, Bombay