The British Prime Minister, the Duke of Newcastle, was optimistic that the new series of alliances could prevent war from breaking out in Europe. However, a large French force was assembled at Toulon, and the French opened the campaign against the British by an attack on Minorca in the Mediterranean. A British attempt at relief was foiled at the Battle of Minorca, and the island was captured on 28 June (for which Admiral Byng was court-martialed and executed). War between Britain and France had been formally declared on 18 May nearly two years after fighting had broken out in the Ohio Country.
What was the reason that the British Prime Minister thought that ware in Europe could be prevented?
{'text': 'the new series of alliances could prevent war from breaking out in Europe', 'answer_start': 71}