The name "Malawi" comes from the Maravi, a Bantu ethnic group who emigrated from the southern Congo around 1400 AD. Upon reaching northern Lake Malawi, the group divided, with one group moving south down the west bank of the lake to become the group known as the Chewa, while the other group, the ancestors of today's Nyanja, moved along the east side of the lake to the southern section of Malawi. Ethnic conflict and continuing migration prevented the formation of a society that was uniquely and cohesively Malawian until the dawn of the 20th century. Over the past century, ethnic distinctions have diminished to the point where there is no significant inter-ethnic friction, although regional divisions still occur. The concept of a Malawian nationality has begun to form around predominantly rural people who are generally conservative and traditionally nonviolent. The "Warm Heart of Africa" nickname is not due to the hot weather of the country, but due to the kind, loving nature of the Malawian people.