on 20 october 1604 king james, who had succeeded separately to the two thrones of england and scotland, proclaimed himself "king of great brittaine, france, and ireland". when james died in 1625 and the privy council of england was drafting the proclamation of the new king, charles i, a scottish peer, thomas erskine, 1st earl of kellie, succeeded in insisting that it use the phrase "king of great britain", which james had preferred, rather than king of scotland and england (or vice versa). while that title was also used by some of james's successors, england and scotland each remained legally separate countries, each with its own parliament, until 1707, when each parliament passed an act of union to ratify the treaty of union that had been agreed the previous year. this created a single kingdom with one parliament with effect from 1 may 1707. the treaty of union specified the name of the new all-island state as "great britain", while describing it as "one kingdom" and "the united kingdom". to most historians, therefore, the all-island state that existed between 1707 and 1800 is either "great britain" or the "kingdom of great britain".