Anne ruled Great Britain.
Anne, Queen of Great Britain . On 1 May 1707 , under the Acts of Union , two of her realms , the kingdoms of England and Scotland , united as a single sovereign state known as Great Britain . She continued to reign as Queen of Great Britain and Ireland until her death . Anne 's Dutch Protestant brother-in-law and cousin William III became joint monarch with his wife , Anne 's elder sister Mary II . Despite seventeen pregnancies by her husband , Prince George of Denmark , she died without any surviving children and was the last monarch of the House of Stuart .