 Complete the following phrase:  By 1650 the kingdoms of Matamba and Portugal had been at war for nearly 25 years, with both sides having become exhausted. Tentative peace talks between Nzingha and the Portuguese began in 1651, would continue in 1654, and would culminate in 1656. The negotiations were aided by Nzinghas recent conversation to Christianity and by the pressure Portugal was facing from its 