The British Isles is a non-period compendium phrase to encompass some or all of the islands off the European coast which have, at different stages, belonged to England (which later, out of period, decided to call itself "Great Britain").
Generally it is taken to cover:
- the Scottish islands, extending to the Hebrides, Orkneys and Shetlands
- the kingdom of (the isle of) Man
- the lesser English islands -- Wight, Lundy and the like
- the Channel Islands -- Guernsey, Jersey, Sark -- which are feudal appenages of the English Crown.
More disputaciously the phrase has also been used to encompass the island of Ireland, formerly an independent realm (or group of realms), then (in period) claimed by England as a conquest; subsequently (out of period) divided, part becoming the Irish Free State, the remainder remaining under English governance, despite republican protest.
Be warned that use of the phrase in this way is likely to cause severe protest from both modern republicans (of either England or Ireland) and "radical" historians, who consider Ireland to have been an occupied country since the English first set foot there, and who view as inevitable the termination of all English influence there, and wish for the payment of massive reparations to the Irish people for what they feel was the illegal occupation of eight centuries.