In historic terms, this refers to a person born from one white parent and one black parent.

Historically, this refers to the term 'Mulatto'

Answer

A mutual defense alliance was a significant cause of World War 1 among the European nations. The alliances were Russian-Serbia, Germany-Austria-Hungary, France –Russia, Britain-France-Belgium and Japan-Britain. A conflict between different groups triggered the participation of another group with interests which resulted to a global conflict. For example the assassination of Archduke Franz Ferdinand of Austria made the other parties (Russia) to be involved to protect its interests with Serbia which made Germany to declare war on Russia and France got involved to aid Russia. Imperialism was facilitated by formation of triple alliances and triple entente because the powerful nations took this advantage to exploit more colonies. A conflict between parties from different alliances was enough to cause war on global scale as observed in World War 1.Other factors that contributed to World War 1 were military alliances, and nationalism.