Final answer:
Napoleon's rise to emperor was largely due to a series of military victories against Austria, which bolstered his reputation and influence in France.
Step-by-step explanation:
The most responsible factor for Napoleon's rise to emperor of France was a series of military victories against Austria. Napoleon's notable rise to power included suppressing a royalist insurrection in Paris, achieving triumphs in Northern Italy against the Austrians, and leading an expedition to Egypt. Despite a setback at the Battle of Trafalgar, Napoleon's successes on land against continental powers like Austria played a pivotal role in his ascension. Notably, during 1805 and 1806, Napoleon secured major victories against Austria, thereby significantly enhancing his reputation and leverage to establish himself as Emperor.