Oginga Odinga had been one of the architects of Kenyan independence. He was Kenyatta's Vice President. But by 1966, the two men had become irreconcilable. Odinga believed Kenyatta was building a government that served the Kikuyu elite and American interests. He resigned as Vice President, formed his own party, the Kenya People's Union, and became the first major voice of opposition in independent Kenya. Kenyatta banned the KPU in 1969 and detained Odinga. It was the moment Kenya's single-party tendencies became unmistakable.