The son of a professor, he was educated at the Friedrich Wilhelm Gymnasium at Cologne, making his theological studies at the University of Bonn and the Academy of Münster.

In 1902 the See of Cologne became vacant by the death of Hubert Theophil Simar [de], and Fischer was elected archbishop on 6 November 1902.

On several occasions during religious or national celebrations he spoke of Kaiser Wilhelm II in very warm terms, which caused much comment.

He declared that "aspiration towards progress, towards the betterment and preservation of earthly well-being is deeply enrooted in human nature and does not contradict the Christian moral laws."

On 13 November 1905, he advised the Catholic miners assembled in Congress at Essen to co-operate with non-Catholic workmen in the discussion of common economic questions.