Fortresses at all the fortified harbors were improved, and the power of the military officials increased as their importance increased, and that of the civil governors diminished.  It was as a direct result of these conditions that the office of Captain General was created, in which the governor shared military and civil authority alike.  Havana fortifications were hastened to completion and the preparations for defense began, which never have been materially improved to this day.  The three fortresses of El Morro, La Punta and La Cabana were built before the end of the sixteenth century and still were standing as the most effective defenses of Havana when our war with Spain began.

It was during the same period, that African negroes were first introduced into Cuba.  Slavery had proved so severe upon the aborigines, that their numbers had almost reached the vanishing point, and there was a lack of sufficient labor for the cultivation of tobacco and sugar cane, the chief products of Spanish agriculture in the island.  It was to promote the production of these new luxuries that the African slave trade was begun.  A royal license from the King of Spain was obtained to guarantee the privilege of importing negroes.

Then began that foul commerce which was another black stain on the history of Spanish colonization of the western hemisphere.  Spanish ships descended upon the African coasts and kidnapped thousands of negroes for service in the Cuban cane and tobacco fields.  The horrors of the trade cannot be magnified and are too distressing for repetition.  It is sufficient to say that in Havana it is understood that the harbor was free from sharks which now swarm there, until they followed the slave ships from the African coasts in multitudes, for the feast of slaves who were thrown overboard on the long voyage.  Scores and hundreds of Africans died during the journey, from the hardships they were compelled to undergo, and Havana harbor itself was the last grave of many of these hapless ones.

Great Britain threatens Spanish possessions.

It was just after the middle of the seventeenth century and during the rule of Oliver Cromwell in England, that the Spanish governors of Cuba began to fear an attack by a British fleet.  A squadron sailed in 1655 with the design of capturing Jamaica, a purpose which was easily accomplished.  That island was taken by Great Britain, the Spanish forces defending it were utterly defeated, the governor was killed, and many of the inhabitants removed, in consequence, to Cuba.  From Jamaica the same fleet sailed for Havana, but the attack was repulsed and the ships abandoned the attempt.  Except for the encroachments of the French upon the island of Santo Domingo, and the continual piratical incursions of French and English buccaneers, the Spanish in the West Indies were not threatened with any more hostilities except by their own internal dissensions until 1762.  At that time Spain and England were at war, Spain in alliance with the French, and it was decided by the British government that Cuba was a vulnerable possession and a valuable one that ought to be taken.