Historiography of the British Empire especially the Royal Navy, was defence of the overseas empire (in addition of course to defence of the homeland). The army, usually in cooperation with local forces, suppressed internal revolts, losing only the American War of Independence (1775–83). Armitage says it became an element of the British creed that: Lizzie Collingham (2017) stresses the role of expanding the food supply in the building, financing and defending the trade aspect of empire building. The first British empire centered on the 13 American colonies, which attracted large numbers of settlers from across Britain. In the 1900s - 1930s period the "Imperial School,"
United States Declaration of Independence against the colonies, "it is necessary that the exercise of every kind of authority under the said crown should be totally suppressed". Adams's preamble was meant to encourage the overthrow of the governments of Pennsylvania and Maryland, which were still under proprietary governance. Congress passed the preamble on May 15 after several days of debate, but four of the middle colonies voted against it, and the Maryland delegation walked out in protest. Adams regarded his May 15 preamble effectively as an American declaration of independence, although a formal declaration would still have to be made. On the same day that