The commerce of the Dutch Republic then covered every sea.

England, to punish the Dutch and to revive her own decaying commerce, issued, by Parliamentary vote, her famous "Act of Navigation," which was exultantly proclaimed at the old London Exchange "with sound of trumpet and beat of drum." This Act decreed that no production of Asia, Africa or America should be brought to England, except in English vessels, manned by English crews, and that no productions of Europe should be brought to England, unless in English vessels, or in those of the country in which the imported cargoes were produced.

These measures were considered very unjust by all the other nations, and especially by the Dutch, then the most commercial nation on the globe.
The States-General sent ambassadors to London to remonstrate against such hostile action; and at the same time orders were issued for the equipment of one hundred and fifty ships of war.

The States-General had not yet ratified Stuyvesant's treaty of Hartford.

The ambassadors were instructed to urge that an immovable boundary line should be established between the Dutch and English possessions in America.
The reply of the English Government was not conciliatory.