From this time on, Portugal was the faithful ally of England, whose sea power during this war gained its vast preponderance over all rivals.

Her ports were the refuge and support of English fleets, and on Portugal was based in later days the Peninsular war with Napoleon.

In and through all, Portugal, for a hundred years, had more to gain and more to fear from England than from any other power.
Great as were the effects of the maritime supremacy of the two sea powers upon the general result of the war, and especially upon that undisputed empire of the seas which England held for a century after, the contest is marked by no one naval action of military interest.
Once only did great fleets meet, and then with results that were indecisive; after which the French gave up the struggle at sea, confining themselves wholly to a commerce-destroying warfare.

This feature of the War of the Spanish Succession characterizes nearly the whole of the eighteenth century, with the exception of the American Revolutionary struggle.

The noiseless, steady, exhausting pressure with which sea power acts, cutting off the resources of the enemy while maintaining its own, supporting war in scenes where it does not appear itself, or appears only in the background, and striking open blows at rare intervals, though lost to most, is emphasized to the careful reader by the events of this war and of the half-century that followed.