Can I use "in the early/middle 20 century" to indicate a certain period of time like it is used here?

Native speaker’s answer
Rebecca
Yes, you can! Although, I'd say it's more common to say "the mid 20th century" rather than "the middle 20th century." Ex: In the early 20th century, the Great Depression happened. Ex: In the mid-90s, sequin and vinyl fabric were popular to wear.