Final answer:
The Half King, a Seneca leader, played a key role in the beginning of the war by supporting the French against the British to protect Native American interests and strengthen the French alliance.
Step-by-step explanation:
The Half King was a Native American leader from the Seneca tribe who played a significant role at the beginning of the war. He wanted to protect the interests of his tribe and maintain their autonomy. In an attempt to trigger the war, he actively supported the French against the British. He did it to prevent the encroachment of British settlers on Native American lands and to strengthen the French alliance.