During all the changes that happened in the government, Blake impressed his men with the conviction that it was his and their business to act faithfully in their respective stations, and to do their duty to their country, whatever irregularities there might be in the councils at home; and would often say among his officers that state affairs were not their province, but that they were bound to keep foreigners from fooling us. These principles rendered him agreeable to all parties, and gained him so generally the reputation of a patriot, that when Cromwell, in his new model of a parliament, left the populous town of Bridgewater the choice of one representative only, they elected Blake. He was also very acceptable to Cromwell, who knew that Blake's concern for the glory of England would influence him to do all, and even more than any other man could be excited to do by views of interest and ambition.

In 1654 he sailed into the Mediterranean, and came in the month of December into the road of Cadiz, where he was received with great respect and civility by the Spaniards, and indeed by all nations as well as the English, who were then in port. A Dutch admiral would not wear his flag while the English admiral was in the harbour; one of the victuallers attending his fleet, being separated from the rest, fell in with the French admiral and seven men-of-war near the Straits mouth. The captain of the victualling-sloop was ordered on board the admiral, who inquired of him where Blake was, drank his health with five guns, and so wished the captain a good voyage. The Algerines stood in such awe of him that they were wont to stop the Sallee rovers; and, in case they had any prisoners on board, took them out, and sent them to Blake, in hopes thereby of obtaining his favour.

He next sailed from Cadiz to Malaga; and while he lay in that road some of his seamen, going ashore, met the Host as it was being carried to some sick person, and not only paid no respect to it, but laughed at those who did. The priest who accompanied it highly resented this, and stirred up the people to revenge the indignity; upon which they fell upon the sailors and beat some of them very severely. When they returned on board the men complained of their ill usage, and the admiral instantly sent a trumpet to the viceroy, to demand the surrender of the priest who was the author of the insult. The viceroy answered that he had no authority over priests, and therefore could not send him. Upon this Blake sent a second message to the effect that he would not enter into the question as to who had power to send him, but that, if he was not sent within three hours, he would burn the town about their ears. The inhabitants, to save themselves, obliged the viceroy to send the priest; who, when he came on board, excused himself to the admiral on account of the behaviour of the sailors. Blake with much calmness and composure told him that if he had complained to him of this outrage he would have punished the men severely; for he would not suffer any of his men to affront the established religion of any place that he might visit; but he blamed him for setting on a mob of Spaniards to beat them, adding, that "he would have him and the whole world know that none but an Englishman should chastise an Englishman."

In 1655 Blake proceeded to Algiers, where he arrived on March 10th, and anchored without the mole, sending an officer to the dey to demand satisfaction for the piracies that had been formerly committed on the English, and the immediate release of all captives belonging to his nation. The dey answered very modestly, that as for the ships and slaves they were now the property of private persons, from whom he could not take them with safety to himself; but that he would make it his care they should be speedily redeemed upon easy terms, and would make a treaty with him to prevent any hostilities being committed on the English for the future.

The admiral left the port upon this and sailed to Tunis, where he sent the like message on shore; but received a very different answer, viz., "Here are our castles of Guletta and Porto Farino: you may do your worst; we do not fear you." Blake entered the bay of Porto Farino, and came within musket-shot of the castle and line, upon both which he played so warmly that they were soon in a defenceless condition. There were then nine ships in the road, which the admiral resolved to burn; and with this view ordered every captain to man his long-boat with choice men, and directed these to enter the harbour and fire the ships of Tunis; while he and his fleet covered them from the castle by playing continually on it with their cannon. The seamen in their boats boldly assaulted the corsairs and burnt all their ships, with the loss of twenty-five men killed and forty-eight wounded. This daring action spread the terror of his name, which had long been formidable in Europe, through Africa and Asia. From Tunis he sailed to Tripoly, and concluded a peace with that government. Thence he returned to Tunis, and granted a peace on terms honourable to himself and profitable to his country.

In 1655 the protector sent Mr. Montague with a small squadron of men-of-war into the Mediterranean to join Blake and to carry him fresh instructions; one of which was to block up the port of Cadiz, in which there was a fleet of forty sail, intended to secure the flota expected from the Indies, and, at the same time, to prevent the flota from coming in without sharing in the riches that were on board. Blake and Montague executed their orders with equal skill and industry, taking care to obtain a supply of fresh provisions and water, as often as they had occasion, from the coast of Portugal. Thither, for that purpose, they had sailed with the greatest part of the fleet, when the squadron from the Indies approached Cadiz. Rear-admiral Stayner, with seven frigates, plied to and fro, till eight large ships came in view, which he presently recognised as the flota for which he was looking out; whereas the Spaniards took his vessels, because they lay very low in the water, for fishermen. This gave him an opportunity of coming up with and fighting them, though the weather hindered four of his frigates from acting. Yet with the Speaker, the Bridgewater, and the Plymouth he did his business; and, after an obstinate engagement, sunk two, ran two more aground, and took two of the Spanish vessels; so that two only escaped.

In one of those that were destroyed was the Marquis of Badajoz, of the family of Lopez, who had been Governor of Peru for the King of Spain, who thus perished with the marchioness, his wife, and their daughter. The eldest son and his brother were saved and brought safely to the generals with the prize, wherein were two millions of pieces of eight. Soon after, General Montague, with the young Marquis of Badajoz, and part of the fleet to escort the silver, returned to England, delivered the bullion into the mint, after which the young marquis was set at liberty. For this success, a thanksgiving, with a narrative to be read thereon, was appointed by the parliament, who issued their declaration of war against Spain.

Admiral Blake continued to cruise before the haven of Cadiz and in the Straits till the month of April, 1657; and having then information of another Plate fleet, which had put into the haven of Santa-Cruz in the island of Teneriffe, he immediately sailed thither, and arrived before the town on April 20th. Here he found the flota, consisting of six galleons very richly laden, and ten other vessels. The latter lay within the port, with a strong barricade before them; the galleons without the boom, because they drew too much water to lay within it. The port itself was strongly fortified, having on the north a large castle well supplied with artillery, and seven forts united by a line communication, well lined with musketeers. The Spanish governor thought the place so secure, and his own dispositions so well made, that when the master of a Dutch ship desired leave to sail, because he apprehended Blake would presently attack the ships in the harbour, the Spaniard answered tartly, "Get you gone, if you will, and let Blake come, if he dares."

The admiral, after viewing the enemy's preparations, called a council of war, wherein it was resolved to attempt destroying the enemy's ships; for it was impossible to bring them off: and to this end he sent Captain Stayner with a squadron to attack them. Stayner soon forced his passage into the bay, while other frigates played on the forts and line, and hindered them from giving the ships much disturbance. Stayner's squadron was quickly supported by Blake with the whole fleet, who boarded the Spanish galleons, and in a few hours made himself master of them all, and then set them on fire; so that the whole Spanish fleet was burnt down to the water's edge, except two ships which sank outright; and then, the wind veering to south-west, he passed with his fleet safe out of the port again, losing in this dangerous attempt no more than forty-eight men killed, and having about one hundred and twenty wounded. It was without question the boldest undertaking of its kind that had ever been performed; and the Spaniards, who are romantic enough in their own conduct, were so much astonished at his, that they quite lost their spirits, and thenceforward never thought themselves safe either from numbers or fortifications.

When the Protector received the news of this glorious success, he immediately sent it by his secretary, Thurloe, to the parliament then sitting; and they, on hearing the particulars, ordered a day to be set apart for a thanksgiving; a ring of the value of five hundred pounds to be given to the general as a testimony of his country's gratitude; a present of one hundred to the captain who brought the news; and their thanks to all the officers and soldiers concerned in the action. Captain Richard Stayner, returning soon after, was knighted by the Protector; nor was it long before Blake and the fleet returned, which put an end to the Spanish war by sea; for the Protector had lately entered into a closer conjunction with France; and, in consequence thereof, sent over a body of land-forces into Flanders, where they assisted in taking the fortress and port of Dunkirk, which was delivered into the hands of the English, who kept it till after the Restoration.