A far more serious dispute arose in the area of the Zambezi valley and Lake Nyasa. Portugal occupied the coast of Mozambique from the 16th century, and from 1853 the Portuguese government embarked on a series of military campaigns to bring the Zambezi valley under its effective control. During the 1850s, the areas south of Lake Nyasa (now Lake Malawi) and west of the lake were explored by David Livingstone and several Church of England and Presbyterian missions were established in the Shire Highlands in the 1860s and 1870s. In 1878, the African Lakes Company was established by businessmen with links to the Presbyterian missions. Their aim was to set up a trading company that would work in close cooperation with the missions to combat the slave trade by introducing legitimate trade and develop European influence in the area. A small mission and trading settlement was established at Blantyre in 1876.