Which Prussian officer turned the disorderly Continental Army into a skilled fighting force

Baron Friederich von Steuben. Prussian officer pushed out of Prussia due to his rumored homosexuality. Washington did not care about the rumors of von Steuben's personal life, he needed a trained soldier who could discipline the Continetal Army. Steuban was able to better train the army for fighting but also cleaned up the camps and taught lower level officers how to prevent disease within the cramped camps.