World War I (1914-1918), a very significant global military conflict substantially centered within Europe, is generally attributed by historians to a combination of significant long-term and immediate causal factors, most significantly including:
- **A)** World War I's own significant causes having no meaningful, describable relationship to significant nationalist competition, alliance systems, or the broader significant tensions already discussed in an earlier unit's coverage of 19th-century political developments
- **B)** A single, isolated cause with no meaningful contribution from any other significant factor of any kind, a characterization that significantly oversimplifies the genuinely complex, multi-causal origins of World War I already discussed at multiple points throughout this unit
- **C)** Significant nationalist competition and Balkan instability already discussed in an earlier unit, a complex system of European military alliances also already discussed in an earlier unit, considerable militarization, and the immediate precipitating assassination of Archduke Franz Ferdinand of Austria-Hungary in 1914 - this combination of long-term and immediate factors illustrates a further significant example of the genuinely complex, multi-causal origins of significant global conflict already discussed at multiple points throughout this unit
- **D)** A complete absence of any significant international tension of any kind prior to 1914, a characterization that directly contradicts the very significant, well-documented international tensions already discussed at multiple points throughout this unit and an earlier unit's coverage of the Balkan Wars and military alliance system
World War I is generally attributed by historians to a combination of significant long-term and immediate causal factors, most significantly including significant nationalist competition and Balkan instability, a complex system of European military alliances, considerable militarization, and the immediate precipitating assassination of Archduke Franz Ferdinand of Austria-Hungary in 1914.