Royal coat of arms of Great Britain

The Royal coat of arms of Great Britain was the coat of arms representing royal authority in the sovereign state of the Kingdom of Great Britain, in existence from 1707 to 1801. The kingdom came into being on 1 May 1707, with the political union of the kingdom of Scotland and the kingdom of England, which included Wales. With the 1706 Treaty of Union (ratified by the Acts of Union 1707), it was agreed to create a single kingdom, encompassing the whole of the island of Great Britain and its outlying islands, but not Ireland, which remained a separate realm under the newly created British crown.

On 1 January 1801, the royal arms of Great Britain were superseded by those of the United Kingdom of Great Britain and Ireland, when Great Britain was united with the Kingdom of Ireland by the Acts of Union of 1800 following the suppression of the Irish Rebellion of 1798.

These novel arms, already in use by parliamentarians in 1648, were adopted by the Commonwealth of England established in 1649.

The Commonwealth of England, Scotland and Ireland (the Protectorate) was created in 1653. St Andrew's Cross was added to the arms in 1654.

Blazon: Quarterly 1 and 4 Argent a Cross Gules (England) 2 Azure a Saltire Argent (Scotland) and 3 Azure a Harp Or Stringed Argent (Ireland) on an Inescutcheon Sable a Lion Rampant Argent (Cromwell's arms). The supporters were a crowned lion of England and a red dragon of Wales. The Scottish unicorn was removed, as it was associated with the Stuart Monarchy. The motto read PAX QUÆRITUR BELLO ("peace is obtained through war").

Following the Protectorate, the 1654 arms were restored.

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