Such a boom came as was never felt before under Protestant flags in tropical waters.

The French, in spite of great exertions, were not yet able to rival the Dutch and English.

These in fact had such an ascendency that when in 1663 Spain revived the asiento by a contract with two Genoese, the contractors must needs procure their slaves by arrangement with Dutch and English who delivered them at Curacao and Jamaica.

Soon after this contract expired the asiento itself was converted from an item of Spanish internal policy into a shuttlecock of international politics.

It became in fact the badge of maritime supremacy, possessed now by the Dutch, now by the French in the greatest years of Louis XIV, and finally by the English as a trophy in the treaty of Utrecht.
By this time, however, the Spanish dominions were losing their primacy as slave markets.