Answer:
1. England
2. Allied powers were formed between France; Italy; Russia; and the United Kingdom
Step-by-step explanation:
The country in which the British and the rest of the Allies unite their forces is ENGLAND (UNITED KINGDOM). This unity was formed in London, England in 1915 to fight the Axis power that composed majorly Germany and its allies.
The result of the Unity formed led to TREATY OF LONDON in which: France; Italy; Russia; and were the United Kingdom formed to become Allied power.