Let's not forget that in the early part of the 20th century, Germany was the powerhouse of mathematics and sciences such as physics and chemistry, to the extent that top scientists basically had to learn German (1) and/or study in Germany (2).
How long did it take Germany to recover that preeminent position?
Its a trick question: they did not recover it.
1) https://hsm.stackexchange.com/questions/162/how-did-german-b...
2) e.g.
> In 1926, Oppenheimer left Cambridge for the University of Göttingen to study under Max Born; Göttingen was one of the world's leading centers for theoretical physics. https://en.wikipedia.org/wiki/J._Robert_Oppenheimer#Early_ca...