Self-Realization Fellowship says that the “Dark Ages” or “Kali Yuga” was between 701 BCE and 1699 CE.

The Islamic “Golden Age”, which was between around 800 CE to around 1400 CE, falls in this period.

The Islamic Golden age saw many advances in science, mathematics, and medicine which later influenced the European Renaissance.

Further Reading:

https://en.wikipedia.org/wiki/Islamic_Golden_Age#Arts_and_culture

https://en.wikipedia.org/wiki/Islamic_world_contributions_to_Medieval_Europe#Medicine