Marcus Rediker in Eurozine:
The origins and genesis of the slave ship as a world-changing machine go back to the late fifteenth century, when the Portuguese made their historic voyages to the west coast of Africa, where they bought gold, ivory, and human beings. These early “explorations” marked the beginning of the Atlantic slave trade. They were made possible by a new evolution of the sailing ship, the full-rigged, three-masted carrack, the forerunner of the vessels that would eventually carry Europeans to all parts of the earth, then carry millions of Europeans and Africans to the New World, and finally earn Thomas Gordon's admiration.
As Carlo Cipolla explained in his classic work Guns, Sails, and Empires, the ruling classes of Western European states were able to conquer the world between 1400 and 1700 because of two distinct and soon powerfully combined technological developments. First, English craftsmen forged cast-iron cannon, which were rapidly disseminated to military forces all around Europe. Second, the deep-sea sailing “round ship” of northern Europe slowly eclipsed the oared “long ship,” or galley, of the Mediterranean. European leaders with maritime ambitions had their shipwrights cut ports into the hulls of these rugged, seaworthy ships for huge, heavy cannon. Naval warfare changed as they added sails and guns and replaced oarsmen and warriors with smaller, more efficient crews. They substituted sail power for human energy and thereby created a machine that harnessed unparalleled mobility, speed, and destructive power. Thus when the fullrigged ship equipped with muzzle-loading cannon showed up on the coasts of Africa, Asia, and America, it was by all accounts a marvel if not a terror. The noise of the cannon alone was terrifying. Indeed it was enough, one empire builder explained, to induce non-Europeans to worship Jesus Christ.
European rulers would use this revolutionary technology, this new maritime machine, to sail, explore, and master the high seas in order to trade, to fight, to seize new lands, to plunder, and to build empires.