Matamba and Kasanje had consistently blocked attempts by Portuguese merchants to penetrate into their lands, and in 1755-56, Manuel Correia Leitão, visited Kasanje and reported on the lands across the Kwanza.
Matamba a Kasanje trvale blokovalo pokusy portugalských obchodníků proniknout do jejich země, v letech 1755-56 navštívil Kasanje Manuel Correia LEITÃO a informoval o zemích napříč Kwanzou.