The Confederate battle flag is usually credited to Confederate Congressman William Porcher Miles , who designed an early version in 1861; the first Confederate national flag (“Stars and Bars”) is more complicated and was reportedly designed by more than one person , including Nicola Marschall and possibly Oren Randolph.

Quick answer

If you mean the famous red flag with a blue diagonal cross , that design is generally linked to William Porcher Miles.

Important distinction

  • Confederate battle flag : associated with Miles and the Army of Northern Virginia.
  • First national Confederate flag : the “Stars and Bars,” with disputed/overlapping design credit.

If you want, I can also explain which Confederate flag people usually mean today and how its design changed over time.