Colored People doesnt mean blacks.. during that time there were "yellow"  which was asian, red which was native american, "black" which negro, "jews" weren't considered to be white nor caucasion, and "white" which was caucasian.  While this debate ravages on, i'll simply place a dubious argument on the page.  You can say who the magazine was started for, but you've provided no proof on who it was started for.   

Since you quoted PBS.  I'll share with you another statement from the same website.  "Du Bois made THE CRISIS into a militant voice in the crusade for black civil rights and for the rights of all people of color"