Question: what caused the british reverses in the opening stage of the war

title: Great Britain in the Seven Years' War
text: Alarmed by the sudden switch in the European Balance of Power the British made a similar agreement with Prussia at the Westminster Convention . By doing this Newcastle hoped to rebalance the two sides in central Europe - and thereby make a war potentially mutually destructive to all . This he hoped would stop either Austria or Prussia making an attack on the other and would prevent an all - out war in Europe . This would allow Britain and France to continue their colonial skirmishes without formal war being declared in Europe . Frederick the Great had a number of supporters in London , including William Pitt who welcomed the rapprochement between Britain and Prussia . The Dutch Republic , a long - standing ally of Britain , declared its neutrality in the wake of the Westminster Convention and had no active participation in the coming conflict .