James was ambitious to build on the personal union of the Crowns of Scotland and England to establish a single country under one monarch, one parliament, and one law, a plan that met opposition in both realms. "Hath He not made us all in one island," James told the English Parliament, "compassed with one sea and of itself by nature indivisible?" In April 1604, however, the Commons refused his request to be titled "King of Great Britain" on legal grounds. In October 1604, he assumed the title "King of Great Britain" instead of "King of England" and "King of Scotland", though Sir Francis Bacon told him that he could not use the style in "any legal proceeding, instrument or assurance" and the title was not used on English statutes. James forced the Parliament of Scotland to use it, and it was used on proclamations, coinage, letters, and treaties in both realms.
James achieved more success in foreign policy. Never having been at war with Spain, he devoted his efforts to bringing the long Anglo–Spanish War to an end, and a peace treaty was signed between the two countries in August 1604, thanks to the skilled diplomacy of the delegation, in particular Robert Cecil and Henry Howard, now Earl of Northampton. James celebrated the treaty by hosting a great banquet. Freedom of worship for Catholics in England, however, continued to be a major objective of Spanish policy, causing constant dilemmas for James, distrusted abroad for repression of Catholics while at home being encouraged by the Privy Council to show even less tolerance towards them.
The co-operation between monarch and Parliament following the Gunpowder Plot was atypical. Instead, it was the previous session of 1604 that shaped the attitudes of both sides for the rest of the reign, though the initial difficulties owed more to mutual incomprehension than conscious enmity. On 7 July 1604, James had angrily prorogued Parliament after failing to win its support either for full union or financial subsidies. "I will not thank where I feel no thanks due", he had remarked in his closing speech. "... I am not of such a stock as to praise fools ... You see how many things you did not well ... I wish you would make use of your liberty with more modesty in time to come".