Who first proposed that disease could be caused by microscopic organisms (germ theory) in the 19th century?

Louis Pasteur

Stollen, traditionally eaten during German holidays, originates from which city? What was the name given to the period shortly after the Civil War ended? What team-based first-person shooter created by Blizzard features heroes with unique abilities? After rising from the dead, for how many days did Jesus appear to his disciples? What is the period of fasting called that precedes Easter?