Besides, if Ireland remained under the dominion of James, the power of William on the throne of England could never have been consolidated.
Although he had met with no resistance on his assumption of the throne, he had the hearty support of but a mere fraction of the English people, and his accession was the work of a few great Whig families, only.

His rule was by no means popular, and his Dutch favourites were as much disliked, in England, as were James' French adherents in Ireland.
In Scotland, the Jacobite party were numerous and powerful, and were in open rebellion to his authority.

Thus, then, if William's position on the throne of England was to be consolidated, it was necessary that a blow should be struck in Ireland.
Torn by dissension, without plan or leading, the Irish army remained, for months, inactive; most of the regiments having, after the northern campaign, returned to the districts in which they were raised; and thus, no preparation was made to meet the army which was preparing to invade the country.
This, ten thousand strong, under the command of General Schomberg, who, although eighty years of age, was still an able, active, and spirited commander, embarked on the 8th of August at Chester, and on the 13th landed near Bangor, in Carrickfergus Bay.

There was no force there of sufficient strength to oppose him.
Schomberg found Antrim and Belfast deserted; but the garrison at Carrickfergus, consisting of two regiments, prepared vigorously for a siege.

Schomberg at once prepared to invest it, and in a short time attacked it by land and sea.