It is an interesting circumstance that what threatened to be a great disaster to Cuba proved in fact to be one of the greatest blessings that the Island had enjoyed since the Spanish settlement. We have already seen how great an alarm was caused at Havana and throughout Cuba by the threatened attack of the British under Sir Francis Drake and how fine a degree of public spirit and unity among all classes was thereby inspired. The threatened attack did not occur, and it was many years before an actual British conquest or even invasion of the Island was effected. But the lessons learned in that period of agitation and after were not speedily forgotten, either in Cuba or in Spain. Therefore, a much larger degree of public spirit and of unity prevailed in the Island, among the Government officers and among the people, while the Spanish crown was awakened to a fuller realization than ever before of the value of Cuba and the imperative necessity of defending the Island if the integrity of the Spanish Empire in the Western Hemisphere was to be maintained. It was then that Philip II began to appreciate Cuba as the bulwark of the West Indies and of the City of Havana, its capital, as the key to the New World. Hitherto Cuba had been nothing but a stepping stone between Spain on the one hand and Mexico, Darien and Florida on the other; and Havana was merely a convenient base of operations and a port of call. But now the immense strategical importance of Havana was realized, while the value of the Island, in its products of copper, wood, sugar, hides and other commodities, was appreciated.
Governor Luzan administered the affairs of Cuba until the end of March, 1589. On that day he was succeeded by Juan de Tejada, a Field Marshal of the Spanish Army. He was selected by the King chiefly because of his military experience and knowledge, and he was the first of the line of governors of Cuba to be known as Captain-General. In him were merged both the civil and the military authority of the Island, so that there would no longer be any such friction as had prevailed between Luzan and Quiñones. Tejada was speedily commissioned by the King to make plans for the fortification of Cuba and also of the other important islands of the Spanish West Indies. He was accordingly accompanied on his coming to Cuba by one of the most distinguished Italian engineers of that age, Juan Bautista Antonelli. Together they surveyed the port of Havana, the port of San Juan in Porto Rico, and that of Carthagena in Colombia and planned powerful defenses for them all. There fortifications were in fact constructed under the direction of Antonelli and to this day bear impressive testimony to his skill.