ompelled to withdraw his troops for home defence and in April, 1666,
was glad to conclude peace with the States.

French naval co-operation against England was also promised; and war was
actually declared by Louis XIV in the early spring of 1666. The real
cause of this strong action was due to other motives than enmity to
England. The death of Philip IV of Spain in September, 1665, had brought
nearer the prospect of there being no heir-male to the vast Spanish
monarchy. The French Queen, Maria Theresa, was the eldest child of
Philip; and, though on her marriage she had renounced her claim to the
Spanish throne, it was well known that Louis intended to insist upon her
rights, particularly in regard to the Spanish Netherlands. He was afraid
that the States, always suspicious of his ambitious projects, might be
tempted to come to terms with England on the basis of a defensive
alliance against French aggression in Flanders and Brabant, for both
powers were averse to seeing Antwerp in French hands. To avert this
danger Louis determined to take part in the war on the side of the
Dutch. The move however was diplomatic rather than serious, for the
French admiral, de Beaufort, never sailed into the North Sea or effected
a junction with the Dutch fleet. Nevertheless, as will be seen, his
presence in the Atlantic exercised an important effect upon the naval
campaign of 1666.

The English fleet was not ready until the beginning of June. The ravages
of the plague and financial difficulties had caused delay; and the fleet
only numbered about eighty sail, including a squadron which had been
recalled from the Mediterranean. The "Generals-at-Sea," as they were
called, were Monk and Rupert. They began by committing the great blunder
of dividing their force. Rupert was detached with twenty ships to keep
watch over de Beaufort, a diversion which had serious consequences for
the English. The Dutch fleet, consisting of seventy-two men-of-war with
twelve frigates, was the most powerful that the Admiralties had ever
sent to sea, not in numbers but in the quality of the ships. De Witt
himself had supervised the preparations and had seen that the equipment
was complete in every respect. De Ruyter was in supreme command and led
the van, Cornelis Evertsen the centre, Cornelis Tromp the rear. On June
11 the English fleet under Monk was sighted between the North Foreland
and Dunkirk, and the famous Four Days' Battle was begun. The English had
only