While Lord Protector of the Commonwealth of England, Scotland and Ireland, Oliver Cromwell set out to vanquish the threat posed by Islamic Barbary Pirates, who were abducting and enslaving subjects of the Commonwealth at sea. A fleet sent by Cromwell brought about the liberation of English and Dutch captives, as well as articles of peace that included protection for subjects of the Commonwealth, including Scotsmen, Irishmen, and Englishmen.
The following is from "White Slavery in the Barbary States" by Charles Sumner:
The coasts of England were now protected; but her subjects at sea continued the prey of Algerine corsairs, who, according to the historian Carte, now "carried their English captives to France, drove them in chains overland to Marseilles, to ship them thence with greater safety for slaves to Algiers."
The increasing troubles, which distracted and finally cut short the reign of Charles the First, could not divert attention from the sorrows of Englishmen, victims to Mohammedan slave drivers. At the height of the struggles between the King and Parliament, an earnest voice was raised in behalf of these fellow-Christians in bonds.
Waller, who was orator as well as poet, exclaimed in Parliament, "By the many petitions which we receive from the wives of those miserable captives at Algiers, (being between four and five thousand of our countrymen,) it does too evidently appear, that to make us slaves at home is not the way to keep us from being made slaves abroad."
Publications pleading their cause, bearing date in 1640, 1642, and 1647, are yet extant. The overthrow of an oppression so justly odious formed a worthy object for the imperial energies of Cromwell; and in 1655,—when, amidst the amazement of Europe, the English sovereignty had already settled upon his Atlantean shoulders,—he directed into the Mediterranean a navy of thirty ships, under the command of Admiral Blake.
This was the most powerful English force which had sailed into that sea since the Crusades. Its success was complete. "General Blake," said one of the foreign agents of government, "has ratified the articles of peace at Argier, and included therein Scotch, Irish, Jarnsey, and Garnsey-men, and all others the Protector's subjects. He has likewise redeemed from thence all such as were captives there. Several Dutch captives swam aboard the fleet, and so escape their captivity."
Tunis, as well as Algiers, was humbled; all British captives were set at liberty; and the Protector, in his remarkable speech at the opening of Parliament in the next year, announced peace with the "profane" nations in that region.
To my mind no single circumstance gives a higher impression of the vigilance with which the Protector guarded his subjects than this effort, to which Waller, with the "smooth" line for which he is memorable, aptly alludes, as
telling dreadful news
To all that piracy and rapine use.
Charles Sumner, White Slavery in the Barbary States (Boston, MA: John P. Jewett and Company, 1853), 40-42. We have modernized the spelling.